BrettG

I had the matching numbers engine build a few months ago and recently installed it. After chasing a few minor issues - had to change the vacuum advance can to get the car to idle when hot, I came across more of a problem.
Car would make a slight metallic sound intermittently - confirmed it was not any accessories such as alternator, water pump, etc.
Pulled valve covers off and confirmed that both rockers for # 1 & #2 cylinders were extremely dry. Each push rod for the two cylinders also exhibited darkening where it rides between the retainer.
At some point in the past someone had cut grooves into the lifter bores, engine builder seems to think that pressure is not getting up to the rockers sufficiently since it may be losing pressure due to these grooves. I went with a solid cam and solid lifters.
Builder was referred by buddy who owns local gas station. Cam and cam bearing have correct grooves.
Can anyone shed some light on the situation?
Builder give me a few options - remove engine, disassemble and have brass lifter guides installed or install roller cam with roller lifters - which have hump to somewhat seal the releif in the lifter bore. Apparently there are no solid lifters that have this "hump" to fill a grooved lifter bore?
Are there some type of valves behind the timing cover which can be changed to improve oiling?

I'm not well versed when it comes to these type of details & I gave bock and complete engine which was in car and explained to him that I want as close to an original 65 396 as possible. Block already had lifter grooves - in hindsight he should have questioned the use of these and the possible implications.

Mark Lovejoy

I can't think of any reason to cut a groove into the lifter bore, in fact I've never seen it.

The right way to fix this is to sleeve the lifter bores, expensive but you mentioned this is the original engine. I suppose oversized lifters would suffice, if such components are manufactured.

I'm surprised the rocker arm assemblies for the two cylinders haven't self destructed due to poor oiling.

BrettG

Luckily I've only driven the car a few times since the install - at most 10 - 15 minutes at a time.

Westlotorn

Since your 1 and 2 are weak or have no oil pressure it leads to answers.
1 and 2 are the farthest from the oil pump. Your leak could be one of the front cam oil gallery plugs or anywhere in the engine. I would look for simple cures before a complete tear down. If you rev the engine the volume of oil increases by many fold and you should overcome the leak with volume and get good oil pressure to the entire engine. If you don't, one way to detect your leak is to pull the oil pan, attach an Oil Pig, a pressurized oil resevoir and pump oil into the oil galleries at 40 lbs pressure and watch where the oil leaks, it will leak down and you can see where it is coming from. What is your oil pressure at idle? If you have a large leak in the lifter bores your idle oil pressure would be weak. If your idle oil pressure is 30 lbs or more all the push rods should be squirting and you have a blockage of some sort. IF your lifter bores are the problem and leaking a high volume oil pump might give you enough pressure to fill the 1 and 2 lifter gallery and pressurize the lifters and push rods. The lifter body has to be in the correct place in the lifter bore or it will starve.
Some lifters have the recessed area on the side of the lifter body in slightly differing places and they can't receive the oil from your lifter oil gallery. Are all your lifters the same brand?

nassau66427

Someone used a lifter bore grooving tool:

"Developed by one of the top NASCAR engine builders, this innovative new tool precisely grooves the lifter bore to ensure that pressure fed oil is directly injected into the contact area between lifter and camshaft. This increased oiling significantly reduces wear on the camshaft and lifters and decreases the risk of premature failure during break-in. This machining operation to the block is quick, easy, inexpensive and is the best insurance for a new camshaft. The replaceable carbide cutters are also available separately. Comes complete with grooving tool, cutter and handle.

Note: The engine must be disassembled to use this tool. Cuts groove from .009" to .012"."

BrettG

I concur but I could not locate any information pertaining to the effects of this groove with regards to oil reaching outer cylinder rockers.

BrettG

anyone??

midyearvette

imo....this should not create a pressure drop enough, not to oil your rockers....the rockers oil from the supply in the lifters through a "piddle" valve that controls oil flow through the pushrods with a small orifice atop each lifter
if you are getting oil to all the other rockers, this is very puzzling to me unless the oil galley plugs are seeping at the front of the mill
i know we are always getting posts on oiling and the early bb's upper ends but if all the many camshaft oiling issues related to these mills are correct, then i would look at the lifters or pushrods in question, maybe look at the oil orifices in the rockers in question
sorry to be so vague but i am stumped on this one....good luck...

Ironcross

Crower offered light weight roller lifters for his camshafts with a small ball embedded in the lifter to keep it from spinning and it was necessary to grove the lifter bore to use them....there was zero oiling problems and no loss of pressure.....using those lifters negated all that monkey motion heavy rev kits and heavy lifters inside the lifter valley....that was a great setup keeping the valve train as light as possible....

Mossy66

I think I would buy one of those oil priming tools that you put in the distributor hole and attach a drill motor to. I would try priming with the valve covers off and see how the oil is coming out of the pushrods, and maybe have someone turn the engine over every once in a while.

That might give us a few clues on what to check next

What is your oil pressure?

markmywords

the grooving is done for even better oiling at high rpm on high performance motors.This would not cause loss of oil to the top end of the motor.If anything it should help it.What is your oil pressure? What oil are you using?

BrettG

I happened to come across these this afternoon, but after speaking with a shop I was advised that these wouldn't help.

BrettG

I had primed the car prior to initial start using priming tool given to me by builder. I was not sure pressure to upper end was adequte(gauge was at 50psi) when turning with drill. Did not see much oil at all coming up rod to rocker. Had builder make trip to my home to review in person - spun engine a few times and did see a little oil coming up and he was fine with that.(also removed drivers side valve cover)

BrettG

I beleive it was 30wt break-in oil he had given to me plus less than a quart of cam break-in.

Oil pressure is circa 50-60 when cold and less when hot - seems to be same as with old engine.

65 Pro Vette

I had the same oiling problem in a 65 -396-425 wiped out 2 cams, until I found I did not have the correct distributor for that engine, there is a casting on the back of the distributor that does not allow oil to go around it, it forces more oil down the oil galleys, the non tack drive verson was used on the 66 chevelle 396, After I found a corvette tack drive one for myself, I saw another one on E-bay it sold for $1,800. You can modify any distributer with JB weld and some sand paper to try it on yours. Give me your E-mail I will take a picture of the chevelle one.

rgs

With the pressure being measured at the typical port near the filter, 50 psi with a drill is actually very good. This points to a blockage. A few clues may point to the issue.

Grovedlifter bores - someone was concerned with lifter oiling. This leads me to believe that the motor was once built for higher rpm operation.

50 psi with a drill - alot of pressure for a drill during priming. Another indicator that the oil is not being bled off through the lifters and pushrods.

I'd be asking the builder if he had removed the oil galley plugs and if so, were they simple plugs or or were they longer restrictor plugs. The restrictor plugs are designed for higher rpm roller applications and limit the flow to the oil galley to keep it in the bottom end. Going back to a stock valve train without removing the restrictors and putting simple plugs in would do exactly what you're seeing.

BLOCKMAN

If that is a 1965 396 make sure the cam has a groove on the rear journal to supply the oil to the lifters!!!

JohnZ

AND has the correct rear cam bearing - if you don't have both the groove on the rear journal AND the grooved 3-hole rear cam bearing, you won't get oil to the lifter galleries. See my tech column below on this issue.

kskid

I remember that Hot Rod mag had a story on grooving lifter bores. Showed the tool used to do it. Don`t remember the reason for it.