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Plug Reads - lean? and/or water - motor pushing water out
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Author:  Falcon67 [ Wed Nov 13, 2019 10:31 am ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

I can't warm the motor even if the cooling system was intact (radiator is already out) - too cold to fire it on methanol. It was 18 yesterday and today. I got it to around 68~70 in the shop and I ain't opening the big door LOL. I just ran the numbers so when I pull the heads I can see if there is any correlation. Seems that the leak numbers are telling me the likely problem is between 2 and 3. 6% seems a decent number for an engine at around 68F. I hear air on every cylinder, but it's passing around the rings into the crankcase.

Author:  DaveMcLain [ Wed Nov 13, 2019 11:56 am ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

I would say that 6% says that it is probably ok but it doesn't mean anything when it comes to the condition of the rings as far as power output is concerned. One time I built an engine for a circle track customer; a very cheap 350 Chevy engine using a cast flat top piston that took the Ford 5.0 ring set. That engine made a little over 400 horsepower with a 4412 and after about 25 pulls worth of dyno work I think it leaked around 5-6%. After a season of running which was probably about 1500 laps on a 1/4 mile dirt track where it won 9 features we put the engine on the dyno. It made about the same power and leaked the same amount. I put in a new set of rings and it picked up about 6 horsepower yet it still leaked about 5-6% after it was warmed up and making pulls on the dyno.

Author:  Falcon67 [ Wed Nov 13, 2019 3:48 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

Extremely interesting observations. Engine makes good power for sure, I was actually expecting higher static compression readings. 180 isn't that wild for 11.8:1, but the PSI reading has to do mostly with the cam speced by Brent.

Author:  Falcon67 [ Thu Nov 14, 2019 9:43 am ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

Left head off -

Little bit of water type stains across the surface. All studs where tight.
Image

Sprayed the deck with WD-40 because there was water around, some likely from pulling the head. There was oil with a bit of water oozing out from the top studs 1, 2 and 3 from right. A lot in the hole for the 2nd from right. Rest look dry as installed. Couple of lower ones have some rust so replacing all. #1 upper right actually looked as if it had combustion by-product on it. Same with a couple of others.
Image

Front side of gasket - I wiped it but you can see liquid marks between top of 1 and 2, some around 2-3.
Image

Back side - lots of goo on the deck between 1 and 2 studs. Pic as lifted off the deck and just flipped over.
Image

I don't see anything in the cylinders except a couple of minor scratches, not seeing any split walls or cracks on the deck. The coating on the piston tops looks like it'll wipe off with a rag and B-12. Don't think I can deck this one anymore LOL without .005 thicker gasket.

Author:  nova467spanker [ Thu Nov 14, 2019 4:37 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

Falcon67
Do you just run strait water or with water wetter? Looks like rust on the water ports.

Author:  Falcon67 [ Thu Nov 14, 2019 7:27 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

Had forgotten to add a rust preventer last time I had the radiator out.

Author:  nova467spanker [ Thu Nov 14, 2019 10:08 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

I want to try the Evans Racing waterless coolant in mine. Zero pressure , higher boiling point and is approved by race tracks. Summit Racing carries it now. Not suppose to eat up the aluminium parts like anti freeze. Maybe you should give it a shot since your engine is all apart

Author:  Falcon67 [ Thu Nov 14, 2019 10:43 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

I have bottles of the Summit coolant additive. I also use only distilled water.

Author:  machoneman [ Thu Nov 14, 2019 10:51 pm ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

Falcon67 wrote:
Left head off -

Little bit of water type stains across the surface. All studs where tight.
Image

Sprayed the deck with WD-40 because there was water around, some likely from pulling the head. There was oil with a bit of water oozing out from the top studs 1, 2 and 3 from right. A lot in the hole for the 2nd from right. Rest look dry as installed. Couple of lower ones have some rust so replacing all. #1 upper right actually looked as if it had combustion by-product on it. Same with a couple of others.
Image

Front side of gasket - I wiped it but you can see liquid marks between top of 1 and 2, some around 2-3.
Image

Back side - lots of goo on the deck between 1 and 2 studs. Pic as lifted off the deck and just flipped over.
Image

I don't see anything in the cylinders except a couple of minor scratches, not seeing any split walls or cracks on the deck. The coating on the piston tops looks like it'll wipe off with a rag and B-12. Don't think I can deck this one anymore LOL without .005 thicker gasket.


That 'goo' between 1-2 does look odd. On a hunch, I'd take a mike to a.) the fire rings around 1-2 and a few others at random. Then b.) mike as well some of the gasket material around 1-2 and again, a few other cylinders at random. I'd also get out the old straightedge and check for head flatness with a feeler gauge.

The 'why' is merely to establish if the gaskets and/or fire-rings are equally compressed around each cylinder. If not, the plot thickens as to stretched studs, nuts backing off, improper head/deck finish (in the 1-2 area) unequal deck height or taper front to rear or other odd findings. Something does seem to be off though and I'll be damned if it's obvious by your pics.

Author:  Falcon67 [ Fri Nov 15, 2019 9:53 am ]
Post subject:  Re: Plug Reads - lean? and/or water - motor pushing water ou

This is what I see on the studs - timely article in Hot Rod

Image

The heads/deck were finished for Cometic, which leaked the first year the engine was together. Brent suggested I just use what I always use, which is the Fel-pro 1013. So those have been on there for 2 years now. It may be a "relaxing" stud that just let contaminants leak in until they finally migrated enough to allow combustion pressure to enter the water. And since I run methanol, I'm fighting condensation all the time. I'll check the deck, but I'd be surprised if it is out of spec.

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