short of having the proper leakdown tester you could pull the pushrods and hook a air hose, maybe 30psi, to a hollowed out spark plug, or a specific made hose used to hold valves shut during valve stem seal replacement. listen for a hiss at the exhaust pipe, intake manifold and oil fill hole or breather hole. try it on several good engines to get a idea of normal sound. smoke originating from the exhaust is not blow by
How to Reduce Blow-By? (modded engine question)
Before you go one step further .... Just give up !!!! Besides all the cheap mistakes you have made your cam purchase is a total failure !! If you had done some research you would know that the 290 lift cam you bought will not work with the hemi head with out modifying the head and will cause even more problems ... And I am sure 18# springs are not what isky specs for that cam .. if you did in fact buy billet parts for this motor and you glazed the cyl. Just go buy another one and start over and ask advice ... It's only $100 bucks
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All this discussion about blow by has me motivated to reduce the crankcase pressure in my 22.88HP Briggs flathead with 300psi cranking pressure! What do you think? Will this give me more power?
All this discussion about blow by has me motivated to reduce the crankcase pressure in my 22.88HP Briggs flathead with 300psi cranking pressure! What do you think? Will this give me more power?
But o.k. I believe you, sheesh.
No cylinder glazing, it has to be the rings. They are staggered as well. Was the first thing I checked after cam install. Maybe I will clean the ring grooves of carbon buildup if it has any.
Only reason i'm using 18 pound springs is because it has less travel than 26s and spring back quicker with less of a p2v near-miss/hit chance(so I feel). 36 #'ers on the way.
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lol, ok, as you can tell i'm not always good at voicing my thoughts and what i've seen.
When I looked into the chamber through the spark plug hole with a flashlight, the P2V clearance looks SO close when i'm pulling the recoil starter. i don't know if at higher RPMs the valve would end up hitting the piston due to the 26#'rs being too weak So I put in 18's for now.
and come on now.. i had to remove the cylinder head to recheck and stagger the rings. dont be like that.
When I looked into the chamber through the spark plug hole with a flashlight, the P2V clearance looks SO close when i'm pulling the recoil starter. i don't know if at higher RPMs the valve would end up hitting the piston due to the 26#'rs being too weak So I put in 18's for now.
and come on now.. i had to remove the cylinder head to recheck and stagger the rings. dont be like that.
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Brent, 26's are stronger than 18's. Piston to valve can only be measure by using clay on top of the piston, rotating the engine by hand, remove the head, slice the clay with an xacto knife and measure with a caliper.
As for staggering the rings, the piston has to be out of the bore. Removing the head won't tell you squat.
I'd suggest removing any good aftermarket parts, spent $100 on another Predator and start from scratch. There are a lot of knowledgable engine builders here. I'm a novice compare to some. The only way to do it is to do it right!!!
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As for staggering the rings, the piston has to be out of the bore. Removing the head won't tell you squat.
I'd suggest removing any good aftermarket parts, spent $100 on another Predator and start from scratch. There are a lot of knowledgable engine builders here. I'm a novice compare to some. The only way to do it is to do it right!!!
Sent from my iPhone using Tapatalk
back away from what? Sounds like you already know the answer so why ask. what does you compression gauge reading have to do with your issue? If what you have stated above you have a cam with unknown specs other than lift greater than .290 with 18 lb springs which on a hemi is not possible and you have 140 lbs of compression so either your compression release is broken, or you do not have one or you used a electric starter and your motor has a stock 24 cc head or low compression. If you are really looking for help try providing us with all the details, like cam specs including lsa, lift duration @.050. what compression, if you do not know at least tell us what has been done to the head as it is not logical that you would be running a stock head with a wild cam. is the motor still 212cc or is it bored or stroked, is it a long rod motor etc.