71OldscutlassS

I can't really understand how the rings could be bad, because the previous owner told me, that he had the engine running only about 1000 miles after the rebuild and then threw an other engine in. When i picked the engine up, even the pistons looked through the plug holes like they havent been running that long. And, they havent been oily or caked, just not like unused. This started after i installed my intake.

Even, i did the leak down test with the engine winter-temperatured garage cold. I dont know how much this affects the results, but i think with a full warmed up engine the results must be better.

when i have the intake back on (hopefully completely sealed) i will do the test with the engine fully warmed up.

skyhigh

make sure you get the MS96009 turkey tray for your 350 if you have an aluminum intake, Eldebrock still has wrong information, they say you need MS96027 but that gasket is for 73 with a bigger crossover etc.

71OldscutlassS

yeah, an MS96009 is already on its journey 👍

Sugar Bear

22% is high but doesn't align with the compression results. 22% isn't necessarily rings, it could be valves and/or rings.

I'd square the intake sealing and the valve seals, run the engine for a while and re-do the leak down test.

Good luck!!!

71OldscutlassS

Yeahy i was wondering too, because its not saying a bad compression on this one.

I have to say that it was my first cylinder leakdown test i did in my life, and i did some mistakes like i let the air forced down some cylinders ( not exact on TDC) and i heard, this would alsp affect results if some cylinders are on a half way down in compression stroke and some others stay up at or near TDC.

Yes, thats what im gonna do.

71OldscutlassS

I was able to change my intake manifold gasket. I sgain used the turkey tray gasket from fel pro without the china wall seals (just a bead of RTV). Used RTV around water ports and Aviation sealant (brush-on style from permatex) on the intake ports. Followed the CSM instructions in bolt torque/tightening sequence.

First, i thought my oil consumtion problem is fixed, but today, i took the car for a longer ride (2 hours driving around town and some highway cruising and with a few 5000 rpm + moments too) just to find out that its still consuming oil.

This is going to drive me nuts.

I haven't take off the carb yet, but i bet, my intake manifold will be oily again under the carb. I Will post pictures.

CAN the Lunati Micro Trol lifters im using be the problem?

Maybe the oil i use (20W-50)is not good for this case of problem (maybe slower drain back, filling up the valve covers, oil sucking through pcv and/or valve guides, umbrella seals are useless wenn being flooded)

maybe i reallx have ro give oil restricted pushrods a try.

I will DEFINITELY check my drain back holes again.

joesw31

When you did your leak down test. Where did you hear the air leaking from? Carburetor, crankcase? Again, 22% is not acceptable. How does oil drainage within an engine equate to oil consumption.

olds 307 and 403

Did you change valve seals? You could try lighter oil, I bet it will use more if anything. It could also be the rings didn't seat properly. One guy with a 403 had that happen. He used a can of Engine Restore and it seemed to work. At this point you are looking at a complete tear down, what will it hurt.

71OldscutlassS

I have to be honest, i haven't really take notice of where exactly the air was hissing off 🤔, i just took a look on how much leakage in % my cheap leakdown tester shows.

I will do the test again with warm engine AND a helper who can hold the engine with a long wrench to prevent it from spinning from the compressed air to stay exactly on Compression stroke TDC.

this was my first leakdown test i did, and as i wrote, it was with cold engine AND pushing down pistons from the compressed air, so i bet it wasnt done by me very accurate.

Im just wondering if this 1 Cylinder with that "not good, but also not really bad" - 22% leakage CAN even cause the consumption of nearly a quart of oil on less than ~100 miles driving.

i called the previous owner/builder of the engine yesterday, just to ask if he know the problem, and he said that on the ~ 1000 miles he had the engine in his car, there was no noticable oil consumption. He said, he couldnt believe that something with the bores and/or rings causes this problem, since the machine shop he had the engine bored is a very recommendet shop. He also told that the rings are moly rings AND that he opened the drain back holes like noted in joe mondello's book.

One of his first questions have been what kind of PCV valve i am using and i was like "chinesium". He said, maybe to route the PCV line through a fabricated canister to check if the oil is really coming from the pcv.



Long story.. first point is to do a proper leakdown test again.

I would hate to tear down the engine again 😮😶

maxi426

A leak down test can be very frustrating to do without the balancer being marked at 90* intervals. Measure the circumference of the balancer, and do the math to mark the balancer every 90* starting at the factory mark. Start at #1 cylinder TDC on compression stroke, then follow the firing order every 90* with the leak down tester. I like the idea of a canister to check the PCV

71OldscutlassS

Thanks for the idea! When i did it, i just followed the firing order and spotted through the spark plug hole on the piston for the best "visable" TDC.

I will definitely try the canister-idea to determine if excessive oil is pulled through the PCV.

Are there "right" PCV valves in case of maybe the spring load in the valve for different years/sizes (350, 455, w-30 etc)?

it would make sense in my opinion, because i bet a 442 with a factory hot 455 makes different vacuum at idle than a 8.5:1 2bbl 350?

i have just anykind (cheap no name) of PCV valve. I dont know if its maybe totally wrong for my engine.

maxi426

PCV valves have different flow rates. Try to locate a correct valve from Standard Ignition or NAPA . Does this engine have factory valve covers?

71OldscutlassS

Today, i did the test with the canister in the pcv-line and the result is that i have more water in the canister than oil. I recognized too, that the coolant level went down. Then i let the engine idle with pcv off and the was excessive steaming out of the breather and pcv grommet.

CAN it be, that i have a major coolant leak to crankcase (intake manifold and/or timing cover) AND the steam of the coolant forces the oil into the PCV? Im pretty sure that its coolant steam, since it has the same taste 😶.

this is how my "pcv canister" looks after driving ~30 minutes. A lot of water with oil sludge is inside:






i tried to take some pictures of the steaming:









This is at idle. I think the steaming could be the reason for the feeling of "high cankcase pressure".

I shot a video of this too. Maybe i can send it to someone in whatsapp? I dont know if its possible to upload a video here?

Thank you all a lot!!

Vintage Chief

The site is not apportioned to facilitate video upload(s) & management - videos are significantly larger than images. Your video would be so small it wouldn't amount to much. The video would need to be <10MB. Your best approach is to upload your video to YouTube then post the link to your YouTube video. It looks like you're making great (methodical) progress on issue resolution.

71OldscutlassS

ok, i uploaded the video on youtube, heres the link:


Yeah, im praying its not the one of the head gaskets or a crack in head or cylinder. Even, that i did the intake twice, im afraid if i find no other leak, i dont know if i can seal the intake better than it curretly is.

BTW, the water temperature is at 180, only when beating the hell out of the engine, it once went up to 190. So i think this is ok.

71OldscutlassS

Any thoughts on the video?

Vintage Chief

Significant amount of steam (vapor, gaseous phase). Take a white paper towel, hold the white paper towel over the valve cover PCV vent (w/ car running) until the white paper towel is saturated with fluid:
(1) In a separate small (preferably white) container:
(a) Squeeze the liquid from the white paper towel into the small container;
(b) Smell the liquid to best determine type of fluid
(c) What color is the fluid in the small container?;
(d) What color is the white paper towel?

EDIT: Leave the fluid squeezed from the white paper towel in the container. Add an equal proportion of regular water to the container & stir the fluids together. Wait 10'-15'. Does the water settle below the surface of the original fluid? Does the water float on top of the original fluid? Is the water miscible with the original fluid? That is to say, do they both fully dissolve in each other at any concentration forming a homogeneous mixture?

joesw31

I watched your video and your engine needs to be pulled out, start taking it apart, and determine the culprit. One more question: Is your engine oil milky?

skyhigh

What about the modulator valve, it can cause white smoke out of the tail pipes, not sure about the valve covers though?

71OldscutlassS

Ok, i will try the paper towel test.

But im getting closer and closer to the opinion that a tear-down is the only way 😒

71OldscutlassS

I think, with a shot modulatur, the fluid in my intake wouls be transmission fluid. And it would cause the engine to smoke out of tail pipes because of the burned transmission fluid.

71OldscutlassS

No, not really.

only a bit at the valve cover grommets, where all this smoke/steam is coming out.

But its not that chocolate-milky oil/coolant mixture

71OldscutlassS

Today i i checked whats coming out of the valve covers right after cold start, and there was NO smoke/steam. Just a tiny bit pressure when i block both valve cover holes with my thumbs. Then i drove the car till the engine is warmed up, took a look under the hood again and then i have the white smoke/steam. So i think my idea that the pressure in my crankcase is from coolant steam seems to be right. tested with some white paper towels, theyre getting water wet/soaked when putting them on the valve cover holes.

The white smoke/steam has to be from coolant, since that my coolant level is definitely going down excessice. My oil filling cap had some milky sludge and the oil filling tube too.

my guess is:

1. Intake water channels (when i had the intake off the second time, i recognized some good rust-pitting around the water ports of the heads, but i thought with the rtv it should be sealing)

2. Timing cover water leak to crankcase (timing cover is new, so no rust/pitting)

3. Blown head gasket(s). What can cause this? The head gaskets are fel-pros with 0.040 compressed thickness.

4. Crack in head/block.

I made some pictures of my endoscope through the spark plug holes too today, seems like number 5,6,7 and 8 have some coolant inside:










i think its time to pull the heads to dig some deeper.
would you guys let the engine in the car an just pulling the heads off? New fel pro head gaskets are already on the way. Can i re-use the ARP head bolts?

this is driving me nuts, i just want to enjoy the new engine, since its running very well.




Greetings from Austria!

Vintage Chief

Having re-read the entire post it's difficult to determine exactly what's going on here - no oil pressure, no oil on dipstick, oil in manifold, gasoline in manifold, low radiator coolant, steam emanating from valve cover PCV vent, Edelbrock intake manifold on iron block, intake manifold gaskets, etc.

My point for using the paper towel is to help determine what steam is venting from the intake manifold PCV vent. Oil, gasoline or coolant. Initially, I suspected you didn't have enough oil to begin with after a change in cam. I still suspect you don't have an oil leak anywhere. Your compression check numbers are very healthy. Edelbrock intake manifolds have a history of poor castings with misalignment issues. Employing correct or incorrect intake manifold gaskets can exacerbate these issues if you have misalignment issues to begin. If your radiator fluid level continues to get lower & you repeatedly need to fill (top-off) the coolant level, you may have a coolant flow (intrusion) issue - somewhere; and, most likely a vacuum issue & oil pressure issue (combined) resulting from intake manifold port misalignment. If the paper towel test (squeezing out the fluid and adding water to that fluid) demonstrates no separation of fluids (oil and gasoline will separate from coolant) then that steam is most likely coolant. Ethylene glycol will not separate from water - never (except at the freezing point of ethylene glycol). The coolant (ethylene glycol) will always remain miscible with water at every concentration - if there's no separation of fluids, then it's most likely coolant. If it smells like coolant, then it's coolant. If it does not smell like oil or gasoline, and if does not separate then it isn't oil or gasoline. Obviously, the converse would be true if it separates and smells like either oil or gasoline. It "appears" to be coolant, but capturing that steam vapor would help to illustrate what's emanating from that valve cover PCV vent. I find it much more appealing to diagnose as much as possible before tearing something down.

Vintage Chief

We posted at nearly the same time. I think you're most likely closer to the issue. I would "still" squeeze out the fluid from the white towel and as I suggested, determine if the fluids separate - but, that's your call. I "suspect" you'll find it's coolant.
IMO, you should never re-use head bolts - never, never, never. Always use new head bolts whenever you tear down heads. Those head bolts have gone through enormous numbers of heat soak cycles and are going to be weakened by simply removing them, and then reinstalling them. Buy new head bolts if that's your direction.

71OldscutlassS

I tried to squeeze it out of the paper towel, but is too less to squeeze something out. It tastes like coolant, but i think, mixed with oil fumes, thats maybe why the staines not drying. I have water drops and milky sludge in the intake grommet too, so im pretty sure that im getting coolant into crankcase.

This is how the paper looks like, and down on the oil filling tube baffle you can see the milky sludge too.

Funny is that theres no sludge on the dipstick, maybe because most of the coolant whos entering the crankcase vaporises (steam out of valve covers).




I would hate to take the heads off, just to recognize that its not the head gaskets. For sure too, because ARP head bolts arent cheap. Im totally with your opinion to alway use new head bolts, i was just wondering if someone thinks its no problem to re use them.

I very suspicious on my intake manifold, since i had it on my stock engine before. Maybe it was a bad idea to re use it.

I put it on the new engine without gaskets, and i thought it fitted good between the heads. Maybe i was wrong.


BTW, i know its maybe difficult to determine whats going on here, i have perfect oil pressure WHEN enough oil is in the engine for being picked up by the pump. I just recognized this whole issues the first time when i was driving around and from 1 sec. To the next, my oil pressure went to zero. This was the point when i recognized first time that my engine has consumed the whole oil and something is going wrong. Then i suspected poor sealing of intake to valley and re sealed the intake manifold again with the 71 CSM sequence and torque and for sure, RTV around the water ports and aviation sealant instead of RTV around the intake ports.

Vintage Chief

If there is misalignment of the intake manifold to the head ports and misalignment of the intake manifold gasket between the intake manifold & head - no variance in sealants is going to address that issue.

olds 307 and 403

Reuse the ARP bolts, there will be no issue. Use their lube for the retorque, if you are worried. Definitely send the heads to have them pressure checked, do not just swap gaskets. Felpro gaskets on iron heads are nearly fool proof. Gorgeous car by the way, I plan to return mine after replacing panels to it's Sherwood Green. Unfortunately it looks like you found the reason this motor was pulled by the original owner, dropping coolant and disappearing oil☹. Sometimes we get deals, sometimes we get other people's headaches.

Vintage Chief

There’s no doubt ARP head bolts aren’t inexpensive. I replaced the ARP head bolts in my F-250 last fall. Certainly not the same as our cars, but the hurt to the wallet still stings.

71OldscutlassS

Ok, i just saw at summit that theyre not as pricey as i thought. 83 $ sounds ok for me. But good to know that they can be re used. Im pretty a newbie in dealing around with issues like that, IF i really pull the heads i will check them very good for any cracks, and check if some shop around here can do the pressure check.

Thanks a lot, i love the color too, never knew that its called sherwood green 😁

I spoke with the previous owner, and he really tried to help me with this issue, since that the engine made no problems as he know. I am pretty sure that I AM the reason for this issue.. maybe its really misalignment of the intake manifold to the heads. Who knows. When i bought this intake about 4 years ago, it was brand new and i threw it on my stock 2bbl engine to convert it to a 4bbl. Never had any issue like that on the stock engine. My previous owner had the same edelbrock intake on the "problem-355", but he wanted to keep it, and i said "no problem, i have the same on my stock engine, you can keep it". Maybe its not sealing proper BECAUSE it was mounted for 4 years on the other engine.. again, who knows 😒.

The previous owner claimed that in his opinion, its nearly impossible that theres a problem with piston rings or head gaskets etc. Since its s very good shop which bored the block and he said he have been very accurate while assembling the engine.

And, to me, he seems to be the kind person which i can trust and he seems to have a lot of knowledge in engine building.

So i dont really believe thats the problem is in the short block or rotating assembly.

again, thanks a LOT to all of you trying to help me finding the issue!!

Vintage Chief

BTW, I wasn’t suggesting bad gaskets, I was suggesting to ensure the intake is port aligned correctly from the get go. Since if it isn’t, no gasket is going to help and a better chance the correct or incorrect gasket could worsen the issue.

71OldscutlassS

Yeah, i was checking with laying the intake to position without any gasket to check the alignment of the surfaces and it looked like its fitting good. Maybe it would be the better way to check with a feeler gauge.

Maybe a new intake manifold could solve the problem? Some said, a performer RPM would ever be better for my setup that the regular performer.

Can it be that the problem is the fact that the intake was mounted on my other engine?

Fun71

I very much doubt the intake was affected from being on another engine. That just isn’t really an issue.


Head bolts can be reused with no issues, especially ARP bolts. These are not torque-to-yield bolts that are designed for one time use. My engine has its original head bolts and the heads have been on/off probably 6 times since the first engine rebuild in 1982. I don’t think you need to remove the heads, though.

I suspect you have an intake manifold gasket sealing issue.

71OldscutlassS

yesterday, i inspected the 2 valley pan gaskets which failed, and recognized that on both of them, some of the positioning bosses who goes into the holes in the heads looked crushed. I dont know why, because i ALWAYS took care that theyre IN there holes 😒.

Then, i took the new (third) valley pan gasket (i ordered 1 again just to be safe) and tested it on my stock engine lying in the garage. And what i recognized is, that the bosses are too long to allow the gasket laying on the head. I dont know if this is a general problem with the valley pan gaskets or i had just 2 monday products.

So, i filed down the bosses to make them a bit shorter, and chapeu, the gasket was lying snug to the heads with the bosses in their holes.

Today, i ripped the intake off again right in my driveway and gave it try #3. There have been definitely a water leak to the lifter valley, i guess only a bit and when the cooling system was hot, because there havent been much coolant in the oil.

I guess, because the coolant was pressurizing my crankcase and steaming out of my valve covers and went to athmosphere, haha.

I really worked exactly, cleaned the surfaces of the heads, intake and gasket, put RTV around water ports and brush on aviation sealant around intake ports on both sides of the gasket, made sure the positioning bosses are snug and completely down in their holes, put a thick bead of RTV instead of the rubber front and end seal, and let down the intake as straight as possible. The torqued as showed in CSM.

Now, i let it sit 1-2 days before filling up coolant to let the RTV dry as good as possible.

if this will not cure the leak, i will try thicker composite gaskets. I red that some just used the valley pan gasket-Pan and cutted off the sealing part of the whole thing to use composite gaskets AND still have a shield to keep oil away from the intake.

are there any composite/thicker gaskets you would recommend? Just to order some to keep ready for worst case 🤔😁

thanks a lot!

olds 307 and 403

The SCE gaskets with the little nitrile beads around the water parts are a nice composite gasket. Here is a link.
https://www.summitracing.com/parts/s...ake/oldsmobile
It could be your intake is warped and may need cut to seal. Also expect sending in the intake to be cut to use composite intake gaskets. Especially if the heads have been cut and the block decked. I managed to use the SCE on an undecked 403 block with uncut #8 heads, a brand new RPM intake and .040" thick head gaskets. Good luck.

joesw31

If I was you, I would do another leak down test and listen where is the air going (Carb, Exhaust, Crankcase). I believe just changing the intake gasket over and over is not very conducive in analyzing your issues.

Fun71

Sounds as if you may have found the issue with the valley pan alignment tabs. Hopefully gasket #3 will be successful.

Vintage Chief

When I did my dry run w/ the Turkey Tray manifold gasket the bosses on my Turkey Tray manifold gasket did not align correctly (in particular in one corner). I made every attempt to make it work until I finally gave in & filed down the one bothersome boss before attempting another dry run. Believe me when I say it was painful working with a 50 pound iron intake manifold with the engine in the car. For the final assembly, I took two normal intake manifold bolts, cut the heads off of them, screwed them into the heads 4 or 5 thread lengths then set the intake manifold after applying RTV to ensure a good alignment.That was 2+ years ago and has been fine since then.

71OldscutlassS

Hello, sorry for not answering for a time, but i lots if work and not that much time to wrench around on my engine.

There are some good and some bad news.

I installed composite intake gaskets (mr gasket 405) in combination with the tray piece of the turkey tray to keep the oil - shield effect alive. Now, no oil anymore is getting sucked into my intake runners anymore, all pistons and plugs are dry, so i think the thicker gaskets solved this problem.

BUT, i still have the darn coolant steaming out of m, valve covers and still loosing coolant.

So, i purchased a cooling system pressure tester and saw that the pressure is really going down. So somewhere has to be a leak. Then, i listened like a doctor with a rubber hose on my ear in the oil filling tube and heard a slightly hissing. I tried to tighten/loosen the bolts of the water pump/timing cover to check if the hissing noise changes, but without any effect, so i dont think that the timing cover is the problem. Then i listened in every cylinder through the plug hole and the hissing was quiet and nearly not hearable in the cylinders, so i assume that the head gaskets are not shot. Then, i took off the valve covers and listened with the hose on my ear in the oil drainback holes and heard the hissing louder and clearly. So i guess the leak is somewhere in the lifter valley, since the drainback holes are going to the valley.

So, long story, there are 2 suspects left:

#1: Intake manifold (again). I guess, my performer intake is simply not fitting close enough between my heads, when i tried a dry test, i was able to push it a bit from one side to the other, so its defenitely not laying SNUG on the heads surfaces. I took a look on my stock engine with the 2bbl iron intake on, and figured out, that there its IMPOSSIBLE to do this there. The intake is laying perfect snug between the heads. I already ordered a new performer RPM intake, since i was told the RPM would be the better choice with my setup. Hopefully this one will fit better. Im just curious why my current performer manifold sealed perfect on my stock engine, but not on my 355. Deck height is stock, and the heads havent been machined. The only difference is that my 355 has thicker head gaskets vs my stock engine with its original thin steel shim head gaskets.

#2:

the previous owner opened the drain back holes in the heads like described in mondellos book. I havent spoke to him of this possibility yet, BUT, i would be going nuts if maybe a Water jacket of the heads was touched when opening these drain back holes 😮😮. I will definitely check that as the intake will be off again.

I just hate this darn water in oil thing.

Greetings from Austria

boese1978

[QUOTE=Fun71;1342237]I very much doubt the intake was affected from being on another engine. That just isn’t really an issue.


Unless that intake was machined at all for fitment on the prior engine.