I just saw an ad for a bore scope that attaches to a smart phone or laptop for $13.99.

E85 shouldn't have anything to do with it If you have the correct spark plugs and a FlexFuel badge.

 

Others have run Seafoam thru the engine to clean things up, had good results.

 

I've watched that vid also, more than once. If you did exactly what he did in that vid, you would not have conclusive results. He went out and bought the cheap tester, didn't modify it to make it useable, and then, when he couldn't get it to work right, just fed 100 PSI(edit: he actually doesn't say how much pressure he used) into the cylinder without any gauges. His test on cylinder 6 only had about 15 PSI, and 100% leakage. His test on cylinder 1 only had about 8 PSI and 50-60% leakage.

You need an accurate leak down test performed. Either modify a cheap one as shown in the link I provided, borrow an expensive one, or take it to a shop. Then you'll know what problem you're dealing with.

 

When I did my leakdown test, even with the valves open, I couldn't hear anything at the tailpipe, so your exhaust valve(s) may be bad, and you may not hear it.

 

No I watched a completely different youtube then. I started with a regulator put a 1/4 fitting to connect air compressor then he put a quick disconnect, but I used a pipe. I created an orifice by using epoxy and drilling it with a small drill bit I think he said he used a 40. I did not have a metric and I can't remember what size I used.
Then that went into my brass t and my second gauge. With the connector to my hose to the spark plug hole.

 

Where did you see the bore scope ad? My care is correct for e-85. I have read some have had issues with it in the south east. I am in Atlanta Georgia.

 

I have also used seafoam. No luck.

 

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Ok, back to being puzzled.

Just to be clear... This means you are leaking 10%, right? Gauge starts at 100 and goes to 90? Not leaking down 90%. But I would expect a lot more than 10% on the cylinder with low compression.

I think we were typing at the same time, you may have missed my post about the exhaust valves.

My bad cylinder was at about 75% of the good cylinders for compression, and the leakage was almost 10x the leak rate of the good cylinders.

Your bad cylinder is much worse than mine, just over 50% of the good cylinders, I would expect much, much worse leakage(like 75-100%). I wonder if you drilled the orifice too big, would it cause these results? The standard is .040" or #60 drill bit, or 1mm. If it were larger, it could cause very inaccurate results.

Here is wiki https://en.wikipedia.org/wiki/Leak-down_tester about half way down they talk about the orifice.

 

I got one of those unsolicited emails. Tmart.com. I'm guessing if they are selling them Harbor Freight might be.

5M 6-LED 5.5mm Lens IP67 Waterproof Android Video Endoscope Borescope Snake USB Inspection Camera

5M 6-LED 5.5mm Lens IP67 Waterproof Android Video Endoscope Borescope Snake USB Inspection Camera
Features Slim and light design, highly portable Connect to Android smartphone directly via micro USB port on the phone Offer a clear view of the interior of machine on cellphone or PC screen The photo and video files can be saved to your Android phone Full-screen app for a clear view and comfortable use
Valid to Apr 25th 24:00 EST, Only 199 Items Left
$13.29 $16.99

 

Thank you for that you are correct about the oriface. I will redo it this week and try again. This really makes good since. I t may take a bit its supposed to rain all week and I am a true shade tree mechanic.