Offshoreonly.com - Excessive blowby and oil leaks

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Yes ^^^^^ see post 7....

Quote:

Originally Posted by ezstriper (Post 4582958)

rings now have a very specific hone finish they need to seal, sometimes guys just hone one way with xxxx grit and call it a day, but that does not cut it nowdays, you have a ring seal issue and need to start with re-ringing and hone to whatever the ring manu. calls for.

I absolutely agree. I already bought a new engine stand yesterday LOL. The problem now is to keep myself from doing a cam upgrade and not leave things alone.

I am running 4.25 stroke dyno'd at 621 HP and the pan I have does have a full windage tray with lots of trap doors to control the oil.

^^^I'd be concerned about your exhaust reverting.

Do you have same pan as Arcticfreind ' s ? I forget what pan part# he has, but his as causing his lower oilpsi at higher rpm's . I'd so a search under his name.

a lot of guys are speculating that the issue is from ring seal,you are just guessing until the engine is taken apart and everything is inspected,i would not be shocked to see a burnt piston causing all the excessive crankcase pressure.

A leakdown test will tell the story

Ok, I pulled the motor as I knew I would have issues and it was easier to do a leakdown out of the boat. I only ended up doing 1, 3, 5 and 7 as that is all the info I needed
1 15% and could hear a little in the crankcase
3 41% and was all crankcase
5 28% and was both crankcase and exhaust
7 40% and was also both crankcase and exhaust.

On 3 and 5 you can see some rust/? on the exhaust valve. A friend who owns a shop lent me this old leakdown tester. Worked pretty good.

So next is to tear it down and see how the pistons and rings look.

Ok, so more exhaust or less cam is called for to keep exhaust water out of top end. But you have had blowby since minute 1. Most likely piston-ring issue. Get the ring grooves checked-measured and replace the rings.

As expected this was the error of the person putting the motor together and that was me. The top ring has way too much clearance, and I have no idea what I did. The question now is do I just use my total seal ring kit I got that is not file fit and do I need to have these cylinders re-honed? The rod bearings look great at least LOL.

What do you mean rain clearance? Up and down in the Piston groove? What is the Piston part number? And what is the ring set part number? There's still a possibility that one or the other of these is metric. Bores ok. A few seconds with dingleberry hone.

Quote:

Originally Posted by dereknkathy (Post 4584094)

Sorry for the incorrect wording, I meant to say ring gap.
These are the pistons I have https://www.summitracing.com/nv/part...-064/overview/
This is a pic of the total seal ring package I got with the pistons from KB/Icon. They are not file fit and I changed rings since I returned these for another set and both sets had .032 ring gap for both top and second rings. Which according to their instructions should be .026 at the most. This is why I bought these https://www.summitracing.com/nv/part...7-35/overview/ and was going to do a fantastic job on my file fit but that ended up being not being the case. The ring sizes are correct I just somehow did the top gap way to big. I am surprised it ran as good as it did.
So question is run these total seal rings? 2 sets had the same ring gap. Is that .032 too much as instructions say .014-.026
do I buy new file fit and put it back together?