Blow By on a fresh rebuild. Possible ?? PLEASE HELP. Pics inside

Sin7; I think the best thing you had said in recent posts is your idea to speak with your friends @ Satche RodShop, and perhaps if you are on a good personal level with one or more of them, you might try to get one or more of them to come over and take a looksie at that #2exh valvestem seal and guide, as well as the others (for comparison purposes) and offer their own opinion on how much of a problem really exists. Obviously, if there's a considerable difference between #2 exh and all other valves and ports on same bank- it is indeed indicative of SOME type of problem. While you certainly need to resolve the baffling issue, I STRONGLY believe there's more to it than that, due to the proliferance of buildup on ONLY that valve and port. It might be as simple as that single valvestem seal, or it may not. But either way- I think you'd be well advised to at least have it checked out "in-person" by someone with familiarity. As others have suggested, I wouldn't even worry about anything in the bottom end yet, as there's certainly not enough runtime on that engine yet to believe that the rings have seated. If 1 valvestem seal can correct it, (the accumulation on #2 exh stem and port), then this could turn out to be a relatively low-dollar resolution, or not. I am sincerely hoping for you that perhaps one of the seasoned members on this site {that may happento live within 90 minutes of Dallas} will see this thread and be able to render you some live assistance, in the event that your friend(s) at the RodShop might not be able to. (I'm hoping they will). Anyways- Think positive! You see already how much folks on here try to help one another out. -Jim


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I feel that Sin7 has 'closed' for the night, and this would not surprise me. He is asking for "advice" and basically being told to 'open his wallet' by some on here.

All he needs to do, is finish the first compression test, and then do a 'wet' compression test, and just post, no pictures, of the difference in the tests.

If he has no "oil", or residue in any other cylinder,and the compression in each cylinder is within 10 percent, of worst to best, it is the #2 exhaust guide, or seal, cut and 'dry'.


I feel the "baffle" has been discussed enough on this thread.

JMO

Nothing like waking up in the morning and getting a dose of information and comedy all at once over a cup of coffee !... man I love this forum...

Back to the topic... I was tied up at work yesterday kinda late so I wasn't able to complete the compression test. Will do that as soon as I get home and report what I find. After the compression tests, I'm gonna drain the synthetic oil, and put in some 10w40 with some zddp just to see what happens over the course of a few days..

Thanks "ALittle1" for those links.

Jim, I'll be calling Sachse Rod Shop during lunch to give them the heads up of what my problems are. However I still want to do as much as I can myself. Like Mikey said, "being curious and motivated" is what got us here. I certainly want to know what caused my problem so that one day down the road I can help the next person out just as you guys have helped me...

BarflyMark- the tranny fluid is perfect.


By the way, you guys can call me by my name instead of Sin7.... It's Luis (sin7 upside down )

This is only one possibility. It could have been installed incorrectly as well.



Any auto parts store. Even the "chain" auto parts will have it. Look in the oil section of the store or ask a clerk.



Could be a leaking seal or a bad guide.

I'd suggest using straight 30wt. non-detergent oil. Be sure to change the filter whenever the oil is changed. It doesn't get cold enough in your area to require a multi-viscosity oil and I don't suggest it for a "new" engine anyway.

The addition of a simple baffle in the valve cover is a very easy job. Do use a thread sealant on the threads to assure that they will not vibrate loose. The blue locktite will work very nicely on clean surfaces.

Thanks

Reading through the thread, I see two problems.

1) The valve covers definetly need baffles.

2) The exhaust valve in question probably has a mis-installed or damaged o-ring.

I would also suggest not using synthetic oil for a while.

I would also not use a straight-grade, non-detergent oil. The 1950s called and they want their oil back.

tom

this question probably has MANY answers based on preference, but what oil should i use based on my situation?...

Non Detergent 30 or 10w40

second, can i use ZDDP with either one ?

I wouldn't be concerned about the ZDDP, the cam is broken in by now. What is wrong with a quality 10w-30?

yea i was having the same trouble too on my 350 i have the exact same valve covers mine are 2" taller than stock, and im also having some smoke issues, everything looks good around the heads i have not tried to adjust the mix screwes yet im hoping thats what it is..

Hey Birdman77

What color smoke, and how much?

COMPRESSION RESULTS ARE IN !!!.....

drum roll please.....

I removed ALL the plugs this time and did a dry compression test...

Cylinder 1 = 145
Cylinder 2 = 135
Cylinder 3 = 140
Cylinder 4 = 140
Cylinder 5 = 135
Cylinder 6 = 135
Cylinder 7 = 135
Cyilnder 8 = 135


So what do I make of this ??... All seem to be within 10% of each other...

This was my first time doing a compression test so I hope I did it right.... The instructions say to let it cycle through 4 compression strokes or until the needle stops climbing.

I'm assuming 4 compression strokes is when i hear the engine cranking/turning over 4 times right?..

During this process i held the throttle wide open....



i did notice something but figured it wasn't right... I tested cyl #2 first and it climbed to 135....without releasing the pressure, my wife cranked it again and this time it shot up to 150.... This is not correct right?

Engine has to turn over 2 times for each cycle, if those numbers are accurate put some brake in oil into it, start it ,let it run at about 15-1700 rpm for 10-15 mins. check compression again and post the numbers.

They should be close to the same or higher if the rings are seating well.

what exactly do you mean by break in oil ?...straight 30w ?

a good mineral based, straight weight oil has worked for me for the last 45 years.

Put a new filter on it, also.