Wise info needed

Hi All,

I've owned my 1970 TA for 35 years. She is all numbers matching and I have about 5k miles on the Ram Air 3 motor since Nunzi did all the machine work. I built it. So, at the end of this summer, I lost oil pressure. At idle she went down to about 10 pounds, so, out she came. Now, Nunzi did some work to the oil pump and he also talked me into the rope rear main seal and because I installed it, it leaks... shocker.

So the inside of the motor looks great, clean, shiny etc... Let me give you the run down of what the engine is and then give you some questions.

Bored 30 over.
Nitrited (sp) crank all done up, rolled edges etc...
TRW L2262 Pistons
I gapped the rings (first time) I will replace those.
Decked and balanced
Nunzi's Street and Strip valve jobs with Nunzi's valves.
Eagle rods and ARP rod bolts
Nunzi's Cam (Crower, not sure of spec at the moment)
Roller tip rockers
Double Roller timing chain

The car is a close ratio 4 speed and I have a 3.93:1 rear. Stock Quadrajet, but tweaked out a little

I'm sure there is more, but that is what I remember at the moment.
So what am I asking all you guys?
I'm gonna replace the rings cause I want them to be perfect and I will very lightly hone the cylinders. What rings do you guys recommend?
I need to replace the cam as there is some weird pitting on at least one lobe. What cam should I go with?
What rear mail seal will give me NO LEAKS and installs mistake free?
I was NOT planning to dip the block due to such low mileage, but what is the best way to paint or coat?
What is the best way to paint/coat the heads?
While the slugs are out, should I send them out to be friction coated?
I was going to buy the Butler Performance Oil pump, the $150 one. Everyone good with that?
Also, I had an engine vibration at about 2k RPM. Nunzi thought perhaps a weight came off the pressure plate, but that does not look like the case. I am gonna replace the clutch and thought I would go with a Centerforce dual disc set up. I'll take opinions on that too.

I think I will take the motor once done to an engine dyne before install.

I think that's it, but knowing me I'll think of more as soon as I hit the "post" button.

Thanks for you help guys. Ask whatever you want  
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1970 Firebird Trans Am (all numbers match) Owned for 36 years
•2012 WRX STI Limited
•2006 VW Touareg V8
•1998 Mercedes E320 Wagon 4Matic
•1986 Alfa Romeo Spider Quadrifoglio

I put a neopream rear seal in my motor. Got it from Ames. Be sure and seal between the back of the seal and the block/cap. Also a light bit of sealer between cap and block from split point of seal to outer edge where pan gasket is. And it won't leak a drop. I use high heat silicone sealer. I also suggest moly rings. The butler pump is a good one. It's been my experience that low oil presure is usually caused by cam bearings. Are you sure the motor really had low presure or is your gage off maybe? While its apart you should consider having it balanced so the vibration is gone. Also I like center force clutches. Jim  
Drive it before your dead!

Thanks for your response Jim,

I really didn't believe the pressure was low, cause it has always been right on the money.  However, I did hook up a mechanical gauge and it confirmed what the stock gauge was reporting .  
Nunzi did balance the engine, but perhaps I will do it again.  I will replace the cam bearings and I will be replacing the cam too.  One of the lobes looks poures.  
-------------------
1970 Firebird Trans Am (all numbers match) Owned for 36 years
•2012 WRX STI Limited
•2006 VW Touareg V8
•1998 Mercedes E320 Wagon 4Matic
•1986 Alfa Romeo Spider Quadrifoglio

hello, you may get a lot of varied opinions which may be confusing and will certainly vary greatly from mine and possibly others. the biggest help i can offer is to make sure you use oil with zddp like valvoline vr1 ir joe gibbs break in oil during break in and vr1 or similar afterwards. do not use synthetic. the synthetic lovers will mow me over regarding this so i will say no more. i love synthetics but obky for the right applications and this isnt it. your oem motor went over 100k miles with conventional oil, what more do you want. go to the post here by pontiacman8 regarding "causes of cam failure" i explained the zddp there in moderate detail "barnett468" followed up by a good article posted by tuffnuff. other informative posts are there also.

the first question is what is your goal? yes it matters a little. does it have headers and intake etc?


rings

lots of racing with a little blow by and smoke included soon then use high perf rings. just good street perf with a good seal no smoke and long life use basic oem cast iron rings. your oem motor went over 100k with no smoke with cast iron rings. it will not do that with most high perf rings. yhe small amount of perf gain you get with them isnt worth the down side.


honing

you may already know this. the block must be honed with the proper grit stone. it varies depending upon what rings you use.  


oil pump

cheap high mellings pump is fine for modest moderate engines. others are obviously good but expensive and overkill. i like overkill but its not cheap


rear seal

don't know if they can do this on pontiacs yet but someone here may. have the block machined for a one piece seal. other than that split neoprenes are easy to install properly. just make sure you remove any pins in the cap or block groove. i clock the seal so it is offset approx 1/4 inch in the block but thats just my personal technique.  


cam

members will need your compression ratio and intended use to make an informed suggest. if you want the same cam you had before, your current cam will have the code on the back which you can use to get the specs from the mfg if you don't already know them. you can also call bruce fulper at pontiacengines.com. phone 909-370-0389 he has some custom grinds. aside from that just install the biggest fattest hydraulic roller you can.comp is good but their lifters suck. crane high rev hydraulics are very good, some places still have them.


engine vibration

just curious, how many grams did nunzi balance it within? it will say on your balance card if you still have it however it doesn't always mean the info is 100% accurate. did he balance your motor with the flywheel last time? how about with the clutch cover also?

no matter what he did you absolutely must rebalance the motor flywheel and clutch cover no matter what. i don't care if it was just done. you have a vibration and don't know what it is. nunzi could have screwed it up, it happens with some guys too often. its not worth risking a vibration simply to save $200 or less. i have fixed dozens of "uncurable" engine vibrations. find a good established race shop to do it or you may be very very sorry. you want a shop that has a machine and operator that can balance it within 2 grams, many machines or operators can't. if they tell you that no one can do that, then just turn around and run. nothings much better than driving a near 0 balanced motor.


clutch

others here will have good suggestions. just check the pilot bearing and front tranny bearing.  


good luck  

There may be a few reasons you lost oil pressure. Check the bypass spring and disk in the oil filter housting. it is there to allow oil to the motor if the filter should ever become plugged. If the spring broke, or the disk broke, it would allow oil to by pass the filter @ lower oil pressure. Most oil pumps have an internal spring to set/limit out put pressure and that may have gone bad also.
There are a hundred different types of rings on the market. Talk to Nunzi and other speed shops to find a combination that works for your needs. I use Chrome Moly rings myself.
If your cam is showing wear, it may be from lack of anti-friction additive such as ZDDP. Make sure you always add some w/every oil change if the oil you're using doesn't have the right content. Lunati makes good cam for Pontiacs, but I am running a Crower with no issues.
While no rear main seal is "easy", like formulajim, I'm using the neoprene one with no leaks. Got it from BOP engineering. They have several items for Pontiac motors. I highly recommend thier one piece, steel reinforced pan gasket also.

I would think the Pontiac factory motor paint should suffice for you block and heads w/ a high temp primer.
For the cost, again depending on what you are wanting out of the motor, I am not sure friction coating the slugs is cost effective.
That Butler pump, while a good one is pretty high in cost. Melling still makes the RAIV oil pump that will put up @ least 60PSI.
Is your engine vibration @ 2K all the time, regardless of whether the vehicle is moving or not? if it only shows up while driving, you may want to look at your U-joints. Typically a vibration @ a certain RPM is either harmonics in the engine (which is a sign your damper is not doing what it should) or a U-joint issue.
The Center force dual friction clutch is the way to go.. I have one and it handles my 428 with over 550 Ft lbs of torque with no issues.

Just my two cents.  
Jim,

+1 my71.
I use melling oil pumps for years with no issues.
The most important thing is to check the bearing clearances and make sure they are correct, because if they are to loose then there will always be a low oil pressure issue.

I never use chrome rings as they are hard to seat and some times never seat.
I always use a good moly ring set on performance builds.
Just be sure the proper grit stone set was used on the hone.  
Engine builder,self taught auto body guy.
Horsepower sells engines and torque wins races

There are two ways to paint metal objects: With catalyst or without.

Typical professional automotive exterior refinish products use catalyzed undercoats and topcoats. That is to say, primer and clear has "hardener" or "activator" in it but color does not. In the case of single-stage (non-clearcoat) paints, the color coat does contain hardener but that product is out-dated and rarely available for DIYers. Catalyzed products are far more dangerous to health than those without "hardener" but they are also FAR more durable due to the molecular crosslinking that occurs during curing. This type product has a "potlife" and actually turns into a plastic coating. You will never rub off the color with thinner.

Uncatalyzed or aerosol spray can coatings have no "potlife". They will not turn to jello in an hour after mixing like catalyzed products. They can often be rubbed off with thinner or gas on a rag after drying. They "cure" slightly by oxidation in enamels and dry purely by evaporation in lacquers.

Which to use for yours? Well of course rattle can etch primer and the correct color blue are available readily from two or three brands. Throw down a twenty or two at a good parts store and you're in business. Buy "real" (catalyzed) body shop paint from an auto paint store and you'll pay a lot more but you will get the wicked gloss and nice metallic. And usually even brake fluid and gas wipes right off, where rattle can paint might stain.

But- in my experience using "refinish paint" on siamesed exhaust port designs, you are gonna get some heat discoloration on the head with the blue metallic. Also on the intake if the heat crossover is active. The pigments can shrug off sun rays better than surface temps. The rattle can stuff may actually do better in those areas because its thinner, more porus (lets heat through better) and may actually contain some sort of high-heat additive. And it looks a lot more like what Pontiac put on there than a base/clear exterior paint job would (not too shiny). Either coating can be ruined by a bad prep job. I like to scrub with wax and grease remover and a red scotch brite (gloves, mask, goggles) then bathe again in degreaser and wipe dry then repeat a couple times. Allow a good long time for all the cleaning solvent to dry off.

If I were spray painting one today I might pick up a can of etch primer and two cans of blue. One good coat of decent etch primer followed promptly by wet two coats of quality engine color, thats it. If you have an infrared lamp around, you could put the parts through a few heat cycles (careful- warm it evenly) before bolting things up so the paint is not so soft.

If I were gun-painting one today, I would use a single wet coat of epoxy primer followed by color coats until covered, then one good coat of clear. Thick coatings peel.

I haven't painted a whole bunch of engines so no brand recommendations here, but now you know the difference in rattle can and pro paint. Search "engine paint kits" and you might find just the system for you at a good price.  

you should have #12 heads. i love my 041 (308/320 advertised 230/240 at 0.50 with  470 lift)cam with crane varible duration lifters in my #62 headed 406 works very good with a 4 spd. with the oil we have now i would spend the money on a roller cam.

zink addedtive is a must or racing oil! any thing that reduces friction helps!

you might check the cam bearings to make shur the oil holes line up with the block. i had a check ball stick in the oil pump. if no other problems are found get a new melling hp pump m54ds $42.00.

ditch the out dated rope seal.

+2 on the centerforce dual friction.

on the ring was there an oil consumption problem. if not put them back in the same hole.

block and heads strip it back down to bare metal. self ecthing primer , base coat with clear worked best for me.

my 0 balanced 406 has the same virbration at around the same rpms it is at least 15 years old and had the crap run out of it. what did nunzi say. i would think he would rebalance for free.  
76 455/4spd TRANS AM
69 GRAND PRIX 406/5SPD

+1 Pman.
Melling oil pumps,(IMO the best made). I have never had a failure either. Just take it apart and check it for any metal burrs.

Rings use Moly 1st ring. Moly is a good choice for the street. Its a tough coating, to handle street grit.  Set all the gaps at .004 per inch of bore.

I'm with Pman check the bearing clearances. Something made the pressure drop. You did try another Gauge so you proofed that. I had a bad gauge act up once.(only once).

For the street stay with the factory bearing clearances.

If the vibration is only at 2,000 RPM and doesn't come back anywhere. I would think it just in the drive-line. If it comes back  push the clutch in. If the vibration goes away its engine related. Purchase a complete balanced flywheel,clutch and pressure plate assembly. When you rebalance the assembly bring all those parts too.

But was the vibration bad enough to hurt the engine bearings. To cause a clearance problem. It only takes one journal for the pressure to drop. Just my 2 cents.

Really check the rod journals, and as you said redo the balance. Was there any metal in the oil pan not from the rods, I was thinking if the crank had a heavy metal piece of balance it could have fallen out. Look at the crank for something odd looking that doesn't look factory. Just a thought.

I just have a little problem with the balance. Did you give the machine shop all the parts for your balance. Antything reciprocating should have been balanced and marked to the oriention it was balanced in. Again just another thought.

If you can still see a Cross/Hatch pattern in the block I wouldn't touch it. If you are using a different type ring as you prior build. Have it honed for that type ring. 3,000 miles usually won't glaze a cylinder wall. Then again who knows?

Bob  

Just some FYI on engine Vibrations. Vibrations will usually square themselves. For an Example only. You have a vibration at 2,000 RPM. (Street Engines)

2,000 RPM is where you notice your vibration. At 70 MPH cruising is 2,000RPM. 72-75MPH the vibration goes away. If it is a true driveline or engine vibration it will come back at 140MPH or 4,000RPM. Even if you had a vibration at 70MPH you won't drive it to 140 to find it again.

  A little story: Back in the day I bought my wife a Brand new 1981 Z28 for her birthday. At 55-60MPH it had a slight vibration. National speed limit was 55MPH. I knew it was in the engine. If I put it in nuetral the viration went away. The dealer didn't want to do anything.
  I was a volunteer fireman. One night going to a fire I started the engine and I heard very loud bang. I shut it off. When I got back from the fire I checked it out..
  Long story short, it had a plastic trans shield. A convertor bolt went through the cover. When I got into it the initial vibration, there was a missing convertor bolt. The Bang I heard was the loose bolt fell out, the three bolt was also loose, but still in the convertor.

  There was one bolt was missing from the factory, the other two were loose enough to oblong the flywheel holes enough. The next morning I called the Dealer (The service manager was also a fireman and a friend). I told him something made a big noise, and a loud bang now come and get it. They were going to install 3 new bolts and send it out the door. I said you going to put a flywheel in it too. It only had 3,000 on it so I wasn't concerned about the engine bearings. My wife used for work, and I figured it would break in 36,000 miles. It did.
  My point was the vibration in your engine severe enough to cause the bearings to wear, and cause a clearance problem? Then the drop in oil pressure.

Bob  

pepsi1:
+1 Pman.
Melling oil pumps,(IMO the best made). I have never had a failure either. Just take it apart and check it for any metal burrs.

Rings use Moly 1st ring. Moly is a good choice for the street. Its a tough coating, to handle street grit.  Set all the gaps at .004 per inch of bore.

I'm with Pman check the bearing clearances. Something made the pressure drop. You did try another Gauge so you proofed that. I had a bad gauge act up once.(only once).

For the street stay with the factory bearing clearances.

If the vibration is only at 2,000 RPM and doesn't come back anywhere. I would think it just in the drive-line. If it comes back  push the clutch in. If the vibration goes away its engine related. Purchase a complete balanced flywheel,clutch and pressure plate assembly. When you rebalance the assembly bring all those parts too.

But was the vibration bad enough to hurt the engine bearings. To cause a clearance problem. It only takes one journal for the pressure to drop. Just my 2 cents.

Really check the rod journals, and as you said redo the balance. Was there any metal in the oil pan not from the rods, I was thinking if the crank had a heavy metal piece of balance it could have fallen out. Look at the crank for something odd looking that doesn't look factory. Just a thought.

I just have a little problem with the balance. Did you give the machine shop all the parts for your balance. Antything reciprocating should have been balanced and marked to the oriention it was balanced in. Again just another thought.

If you can still see a Cross/Hatch pattern in the block I wouldn't touch it. If you are using a different type ring as you prior build. Have it honed for that type ring. 3,000 miles usually won't glaze a cylinder wall. Then again who knows?

Bob

Well (Pepsi1)Bob with all due respect, your info is wrong again, as is too often the case.
I really wish you wouldn't post incorrect info.

A moly faced ring is actually the worst for dusty conditions. It has a somewhat pourous face that's desgined to hold the oil that the wall doesn't.
A chrome ring gives the best insurance against dust but as Pman mentioned they take forever to seat, if at all.


Hope this helps.  
Mark
Engine builder, located in Central Florida

Mark, I thought the job of a good air cleaner.,. along with a good pre- cleaner element would keep "dust" out of an engine.
After all, many diesel engines, operating in severe dusty conditions rely on this multi element system.
Plasma moly rings are the preferred choice of pro engine builders.,. quick seat in time is relevant.
Calling Pepsi (Bob) out is rather rude.,. don't you think.

 
When The Flag Drops,,,



The Bull Chit Stops,,,


P. Engineer, Engine Builder

Hello here's a few more ideas. not trying to step on any toes these are just my opinions only.

vibration and engine balance

you must rebalance your motor, here's why. rowsley and pepsi1 have brought up good points regarding possible drive train problems causing your vibration. these points are obviously good however your motor is out therefore you cant go back to check for it. i'm going to take a guess by your post that you have eliminated the possibility of it being the drive train or a bad motor mount, is that right? either way it doesnt much matter, in the end does anyone really want to reassemble their motor as is knowing they had a vibration somewhere in the car just to find out it was the motor all along then take it all apart again to balance it. if it was only at a certain engine speed like it sounds it was then it is in your engine and is definitely a harmonic problem. i have never had a harmonic problem in a drive train/chassis [motor excluded]. if it was in the wheels, driveshaft balance, trueness, u joints or rear diff yoke then it would get worse the faster you went.

harmonic engine vibration and harmonic dampers

this is very complicated so i will try to simply it. you can find a lot more confusing and semi contradictory info online regarding the best dampers. all engines have harmonic vibrations. a harmonic damper is "tuned" for a certain vibration frequency. a stock damper can only cancel harmonic vibration at one frequency [rpm] in general. when you rebuild your motor and replace your 3 lb stock pistons with featherlight srp's then your motor will vibrate at a different frequency than it originally did. your origional damper is not tuned for this new frequency so your newly balanced motor will still vibrate some but at the new frequency. if it is noticeable then the only way to fix this if you have this problem is to buy an aftermarket damper that cancels harmonics over a wider range than the stock one. now the new problem, well which one is best. more complications here since they all damper mfgs think they are the best of course. i'll try to simplify this also. there three main mfgs. dont buy a cheap chinese one. ati polymer, fluidampr liquid, tci rattler pendulum. ati std damper has two inertia rings and two rubber insulators, it dampens at least twice the harmonics as a stock one, $450 balance with motor. fluidampr has silicon fluid inside with one inertia ring it dampens wide range of harmonics dont use on most motors over 600hp, you can not balance it with the motor but you dont need to $450. tci pendulum they claim to work over entire harmonic range but rattle when you turn your motor off $325 probably cant balance with motor check with mfg. not cheap but how bad do you want to get rid of the vibration. if your stock one is good you can balance with that first. if it still vibrates then you can buy one of these above. you might save an unnecessary purchase this way.          

balance cost

if your motor is already properly balanced then a reputable shop should charge you about $70-$100 only to rebalance it because it takes less time to do it.


variable duration lifters and cam types

if you use solids you don't need to worry about them, they are hydraulic only. i personally dont use them and dont care for them much but thats just me. i have had cars with them. they are not used by many people and are out of the mainstream a bit. i prefer to stay more on the well beaten path. some brands are noisy like a solid cam with a very loose adjustment. this is typical with the old school "rhoads" lifters. simply put they leak oil untill they build rpm. this makes the cam seem smaller than it actually is at low rpm. the basic theory is that you can run a huge cam without sacrificing bottom end. i prefer to just by a cam that suits my purpose instead of trying to make two cams out of one but thats just me. you should ask rowsley what brand he has and if they are noisy if you are considering them. a soklid will give you the most hp and throttle response. if you want a solid but don't want the rocker noise then check out comp cams "tight lash" series. i have used several of them with no noise whatsoever. if it were me i would use a solid roller. without question they deliver the most overall hp and throttle response. the roller helps insure your cam wont go flat and reduces friction [drag] so they generate less heat, increase hp, increase peak rpm, increase the speed at which your motor builds rpm and increase fuel mileage. this actually allows one to use a smaller cam when compared to a non roller to get the same hp, but they are very expensive compared to a hydraulic non roller.    

cam oiling passage

i found this post from rowsley and thought it reasonable. if you do this you will need to make sure it hasn't been done already.

"you can also drill the oil feed hole a little bigger in the upper main bearing when using a high presure oil pump. i don't remmber the drill sized i used or were i read this. i do this to all of my pontiac motors."
 

piston rings

i personally would not use the same rings. yes it "may" be ok. it does work sometimes, however its not worth the gamble for another $40-$80 is it? i have nothing against moly rings, i have used them a lot but if your driving it daily i would still use cast iron, they will seat quickly with no problems guaranteed and last long without smoking. molly rings are the most commonly used.


oil pump drive rod

use a heavy duty one.


engine paint

for rattle cans, the best i have in my area is martin senour. covers xlnt, run resistent, decent heat resistance. your parts store can order it.


oil pump with part number

i just read your post again after i typed this so i realize you already know most of this info on pumps, sorry about that. i would say that the your choice is very good but a little over kill if you're trying to build it on the cheap. i'm starting to think that you are not though. if butler has all these diamonds to polish a pump with he must be doin pretty well!

looks like some agree with the roller cam and mellings oil pump brand suggestion i posted but these are pretty common favorites from my experience anyway. opinions may differ on the hv vs hp type however. either one will save you money which you can use towards balancing your motor. the following string will certainly confuse you so look at the one below it. you can go all out and probably get a pump that is both hv and hp if you really wanted.

http://www.camaroz28.com/forums/lt1-based-engine-tech-9/high-volume-vs-high-pressure-oil-pump-736547/


look at this from this site on mellings and butler pumps good info.

http://www.highperformancepontiac.com/tech/hppp_1109_oil_pump_observations/viewall.html

summit racing or butler racing melling m-54f is oem 455 sd and ra IV 400 high pressure pump at 70 psi, std volume, price at summit 49.95 info says std volume std pressure but that means for the high perf oem motors. a stock pump for a 2 barrel etc is m-54d as per the string above above.


valve seals

i would use pc seals on the intake valves at least, however you may already have them.


valve leaks

wouldn't hurt to spray some contact cleaner or similar down the ports just to make sure the valves aren't leaking. they're already sitting there in front of you just waiting. it just takes a minute, you never know. if i saw any leaking at all i would lap in the leaker's or repair as needed. some others think a small leak is no problem and would consider fixing them unnecessary and excessive.  


valve guides

if you take your heads apart for some reason and find your guides are knurled [probably not] then you should replace those guides and regrind the seat and valve. knurled guides leak oil and wear out very quickly.


Your talkin about an original ra motor why take chances?

my best suggestion is to simply sell your outdated worn out old car to me and buy a newer model, how about that?  

BALANCER THATS GOOD TO KNOW. I STILL HAVE THE STOCK BALANCER. MY VIRBRATION WAS THE MOTOR . I UNBOLTED THE CONVERTER IT WAS STILL THERE.
AS FOR THE OIL PUMP JEGS CATALOG STATES 698-M54DS HIGH PRESSURE/W SCREEN $41.99 WITCH MAY BE WRONG. I DID NOT KNOW ANY BODY MADE HV PUMPS FOR PONTIAC. I WAS TOLD THERE WAS NO SUCH THING AS HV FOR A PONTIAC ONLY HP. BUT THAT WAS A LONG TIME AGO AND THINGS CHANGE. WOULDN'T THAT BE LIKE FEEDING A 1" HOLE WITH A 2" PIPE.  
76 455/4spd TRANS AM
69 GRAND PRIX 406/5SPD

hi rowsley thanks for your the info you posted on my pink firebird questions etc. its late so i'll try to make this short and somewhat coherent. i have not looked at jegs i can only guess that s means new screen dont know what 698 means. i did look it up briefly and jegs says it is also for hp motors so there is some discrepancy. my info came from summit and the string i put in my post. looks like a call directly to mellings is needed. but i think jegs is wrong. why would butler modify a stock pressure pump? i also have not seen an hv pump for a pontiac but i haven't built one for a while. i have used them on other cars so i just guessed they would be available for these also. your "hole" question is a good one and the short answer in this case would be not necessarily. only the factory and possibly the oil pump mfgs know how much oil one can flow through their systems. does the stock pump flow more than the system can handle. hard to say. i do know that on some of the hv pumps i have used, the hole in the pump has been the same size as the hole in the block, it has also been the same size as the hole in the non hv pump. this means the hole in the std pump is large enough to flow more oil than the pump can pump through it. hope that answers your question.


engine vibration fan or water pump

as far as the balancer goes it is a ton of money. if you do buy one and it doesnt cure your problem than you can always resell it on ebay for a small discount however if it doesnt fix your problem there is something else going on like engine balance, fan blade or water pump etc. had that problem before a few times. try taking the belt off and starting it. let me know if that fixes it.    

thanks