Had 15psi hot idle with 50wt oil and e.o.s. Had 40psi hot at 2500rpm on freeway. Went whole summer like this with clean oil. Changed oil to winter weight 10w-40 and e.o.s. Two days later, yesterday, pulled thru second gear and promptly lost oil pressure. Oil clean. No leaks. Then had no psi hot idle. And, had 20psi max. Limped home 1.5 miles with bad things happening under the hood. Valvetrain noise and misfire evident when shut off in driveway. Something let go all at once. I think cam bearings overheated and came apart in the block. I'm 34 years old. I'm a professional mechanic at a Ford dealer. My first car was a '67 Spec 400/glide/2.93. Been fighting Buick oil pumps for a long time now. I'm tired. I refuse to buy a new timing cover and pump from TA Performance. That's about $700.00. I think that is not an acceptable fix...it will grenade, also. I'm tired of putting it in neutral at traffic stops to keep oil pressure up above 15psi. I'm tired of having to run 50wt and e.o.s. to make acceptable pressure. I'm tired of wiping out expensive camtrain parts over and over. Does ANYONE have an ideas on improving our beloved 455's oiling system for the average guy? Remember, nobody can help us locally because nobody builds Buicks locally with any good results. I want to end this frustration and use a dry sump pump. That would be an enormous tast to fabricate and install. What about a power steering pump for an oil pump? I'm desperate. Who can tell me how to fix our problem. Give me ideas. Don't tell me about how good your new TA front cover is. Does it make 40psi hot idle 600rpm with 10w-30 in the case like brand-x? I didn't think so. Come on guys. Who is really satisfied with their buick oil pressure? Like all of you, I have a tremendous amount of money and time wrapped up in this engine. I'm not about to give up, or in.
mine was # 2 cylinder exhaust rocker shaft broke. This allows the lifter to come out of the bore and all oil gushes through the hole. See my post of yesterday. Good luck
Dick Cerdinak of Portage Performance did an excellent job with all machine work on this engine. He told me the crank and rods were set loose at .003" to .004". He hand sized the cam bearings (TA external groove set 3:00 and 7:00) with a homeade tool to make sure the cam (TA510) spun freely with no excess. He hand drilled piston wrist pin return ring oilers for high rpm usage. The motor is balanced flawlessly. He was 60+ years old at the time he did my engine and is well known for his Ford work. He raced the factory numbers matching classes with his '69 Boss 429 hemi mustang (10.80s with a 242* cam). While I was in his shop, a guy came in from Hawaii to pick up some stock crank Ford 351 motors that were positively mean. Dick is like a Jim Weise. Not to be questioned. Some guys can mess up an engine with a $40,000 machine. Other guys can do amazing things with a $8.00 file. I know the machine work was loose. It was by design. I know this puts a lot on a Buick oil pump. But, given enough oil volume to the bearings, this motor will live and live well. I need a serious oil pump.
Ken, You simply can't build a BBB with those kind of clearances, and expect satisfactory oil pressure, simple as that. This guy may build a hell of a Ford engine, but he doesn't know anything about Buicks. There is a reason Buick built their 455's with Main and Rod bearing clearances limited to .002. That big 3.25" main journal crank, generates tremendous bearing speeds at high RPM. If you don't have sufficient oil pressure, you end up starving the rod bearings. The front mounted oil pump can only supply so much volume, and oil pressure bleeds down from front to rear of the block, especially with loose clearances. Add to that, the fact that the oil pump clearances increase as the motor gets hot, only compounds the oiling problem. BBB's will last forever if they are built right from the start. You will need more than a stock pump to lube your motor, At least a HV/HP pump kit, which has it's own downfalls. I would pull the motor apart and correct the clearances before it self destructs.
Yep, you need a specialist when building a Buick. Id say maybe 10% of all builders know how to do a Buick right as most treat it like just another Gm motor.
You guys are right. Motor is coming out for inspect. Going to fabricate a Peterson single stage external wet sump oil pump to block on passenger lower front by crank pulley. This will end all oil pressure problems and will allow my looser clearances. That's the plan for now. Thank you for your tech help.
why not fix it right and have the crank ground for .002 -.0025 clearances and be done with it? there are guys running stock pump assemblies with booster plates and adjustable oil pressure regulators with well over 500 hp and no problems. just my opinion but i think going to a different oiling system is just a bandaid with .004 clearances with those types of clearance and a higher volume of oil you are going the be hemmoraging oil from the mains and not gaining a thing. might even lose a bit of HP due to all the oil swirling around the crank. just my thoughts on the issue...
there is also the risk of cam n cam bearing damage if its not regulated right. Its why the adjustable regulator is a must for the Buick. There have been a few ruined by hi vol pumps.
The mains and the rods are the last to get oil on these motors...Most rod knocks end up being either #7 or 8 because those are the very last thing to get oiled on these motors...You will be hemorraging(sp?) too much oil before it even gets to the back of the motor...Buick intentionally kept the clearances tighter so that the oil pressure would stay up until it got to the back of the motor...
I agree that the guy that machined the parts did not do a good job. He assumed everything would be fine at those loose tolerances, NOT!! Have the clearances brought back into BUICK specs. and be done. Its tough finding a machine shop that will actually research the correct tolerances for Buick engines. A machinest at a machine shop was actually quoting the clearances for a Buick at .0035 for the mains, and that was right out of his manual :rant: I pulled my parts out of that shop fast :3gears: Mark
Low oil pressure at an idle is really no big deal as long as it comes up with the revs. I used to get about 8 lbs at a hot idle but it would shoot up with the revs reaching about 70-75 lbs at 5500. I will be honest I built my motor in my dads garage and never checked any clearances so I was probably very lucky that it didn't blow apart the first time I ran it through the gears but I drove it for four years that way and it was still going strong when I sold it.
Cool it! Another suggestion to add to the mix of excellent suggestion already posted on this thread. COOL IT :bglasses:. I just installed a 600HP oil cooler on my vehicle and had thefollowing results. 10w40 Motor oil Pre-cooler - 12LB at hot Idle/42 lb @ 2200 RPM/ 65-70 at 6000 RPM Hot Post-cooler (after several 5500 - 6500 blasts) - Idle 25 lb/60lb 2200RPM/ 75- 80@6000RPM Oil temperature 170* A side bar note: I also eliminated the Accusump system I used due to the fact that the oil cooler is higher than the oil pump and gravity bleeds oil front the 6' of coller tubing (added volume) into the pump when at rest. This keeps the pump in a primed condition on cold starts. It used to take 3 to 4 seconds (depending on Air Temp and remote oil filter) to get oil pressure to the gage at the back of my engine, that time has been reduced to 1-2 seconds. The remote oil filter is now near and below the oil pump. What a relief, finally I can limit the amount of time I watch my oil pressure gauge and enjoy the ride. Weekender :3gears:
Turned out to be a loose oil pickup tube. TA's 8qt pan set. Need to bracket the end of the tube to a main cap or something to prevent vibration. Main bearings wiped. Rod bearings look OK. Rings sharp. Tube came loose gradually from first day of driving new motor in 2002. Was fighting this problem for a long time and never knew it. Kick in shorts?
While a little bracket to the #4 main cap won't hurt, I wouldn't prolly expect that to cure all the issues. As a few guys said, keeping the bearing clearance on the mains a little tighter is the key to good oil pressure. I have build 20 something 455's in the last couple years, and I can maintain 25-30 psi with even a stock oil pump, modified correctly, with a booster plate, as long as you keep the mains around .002 to .0025. Easier to do this with a TA cover, although I always just by the bare cover, and build my own assembly, with a modified pump cover and booster plate. The reason is simple.. area. The 455 has a 3.25" Main journal, if you do the math and figure how much area there is available with a .002 clearance (and we know that a "P" bearing actually gets thinner as you move from 90* verticle to the parting line, so .004 at 90* could be .0055 up near the parting line). Then open up that .002 to .004 (using those figures just for example) and you will see how much more area you are exposing to allow oil hemorage, compared to say a 2.75" main dia motor. Rods are nowhere near as much of an issue, as thier hemorage is controlled by the amount of oil passed to the rods thru the crank. Rod clearance will very rarely affect oil pressure to any great degree. Adaquate rod side clearance, and round main bores are the key to keeping the rods alive. The biggest single factor in getting a 455 to live, is round, straight main saddles, and it is the number one thing that machinists not used to doing these large housing bores have problems with. Make sure the mains are round, I would spec a 3.4380-82 housing diameter with a low limit crank grind to get the clearances where you want them. But make sure you actually take the time to install the main bearings in the block, and measure each bore with a bore gauge. Bearings do vary, especially between manufacturers. You can go nuts and build that external oil pump setup for a street motor if you like, but it's really not that hard.. JW
Ken, I was going to reply early on in the thread that maybe the oil pickup tube had come loose. My engine is at Earick Racing now because of the same problem. Look real close at the cam bearings with a light from behind the engine and be sure they aren't damaged. Mine were melted and I could not get the cam out. The mains and rod bearings looked ok. I probably have less than 2500 miles on it, boy does that hurt. Good Luck, Mike D.
