Topic: Compression HIGHER in one cylinder??!!?

[grumpy]

My 750K3 had low compression in #2 all summer and it had oily residue on the end of the exhaust pipe. Adding oil to the cylinder got the compression up to normal. Sure seemed like it needed rings. Add that to the winter to-do list.

Well, the oily residue stopped appearing a couple of weeks ago. Hmmm. Maybe I got lucky and it was a stuck ring that worked itself free.

Did a compression test today and #2 was 30% HIGHER than the other 3. Repeated tests gave similar results.

HIGHER    WTF?!??!?!  ?

[bryanj]

All the oily crap burnt onto the piston crown and head reduces the size of the combustion space

[KingCustomCycles.com]

The mystery of compressions.  Temperature of the engine will dramatically change the results, ring end gaps lined up will drop compressions to near zero, rings that stick and unstick will vary results.  I say drive them until they fix themselves, or the need for work is clear and evident.   

[HondaMan]

Try this: get a can of BG44K and divide it into 4 equal, sealed containers. Add one container to each fillup, 4 in a row. Make sure to run down past reserve for each fillup, or skip one in between. This trick stuff will clean those crowns and valves, too, and let the rings spin again. It's some of the only snake oil I use, and pricey, but works.

[Soos]

Try this: get a can of BG44K and divide it into 4 equal, sealed containers. Add one container to each fillup, 4 in a row. Make sure to run down past reserve for each fillup, or skip one in between. This trick stuff will clean those crowns and valves, too, and let the rings spin again. It's some of the only snake oil I use, and pricey, but works.

I'll agree that stuff will EAT carbon.
Engine machine shop I used to work at had a bucket of the stuff, pour it into a glass, and throw in 2 of the nastiest valves I have ever seen, and in 24-48 hours the carbon would start falling off.
swirl them around, and they come out pretty darned clean.
A rag is all it took to get the really stuck stuff off at that point.



WELL worth the money if you want to remove your carbon deposits.


l8r

[Soos]

Try this: get a can of BG44K and divide it into 4 equal, sealed containers. Add one container to each fillup, 4 in a row. Make sure to run down past reserve for each fillup, or skip one in between. This trick stuff will clean those crowns and valves, too, and let the rings spin again. It's some of the only snake oil I use, and pricey, but works.

I go a bit different, but have actually not used it on a bike yet.
my cars, and my van yeah.
I like to soak it repeatedly through the intake.
I get it running then flood it badly enough it will not run, let sit a weekend, flood it again so bad it wown't start(crank it just long enough to dump in a whole can), let sit 3-5 days.
After that I like to run the motor a bit(10-100 miles) and change the oil, filters and do other tune up stuff I need.

You should see the things I have seed doing this dislodge.




l8r

[grumpy]

.. drive them until they fix themselves, or the need for work is clear and evident.   

That might be what I just did 

I was thinking of getting a used (cheap) borescope off evilBay to take a look thru the plug holes. I can see the tops of pistons 1 & 4 and they are pretty black and crusty.

Sooo.. BG44K
Looks like the only sell it at auto dealers. That's kind of odd.
Says the Ford dealer in town has it. I'll go check their parts counter - IF make it past the pack of desperate car salesmen ...
What's in that stuff? Hopefully it won't eat gaskets and hoses!!!

[grumpy]

I found the MSDS for 44K:

http://www.bgfleming.com/products/msds/208.pdf

What about Redline SI-1:

http://www.redlineoil.com/msds/49.pdf

Seems pretty similar.

Actually, I should just go get a 1/2 gal of diesel...

[dusterdude]

atf

[HondaMan]

I found the MSDS for 44K:

http://www.bgfleming.com/products/msds/208.pdf

What about Redline SI-1:

http://www.redlineoil.com/msds/49.pdf

Seems pretty similar.

Actually, I should just go get a 1/2 gal of diesel...

I like to use diesel as a parts soak.
NAPA auto parts sells it around here, at $1 less per can, than Checker, who is always out-of-stock and the most expensive nearby.

Soos: did the BG44k-in-a-bucket evaporate? I mean, the volatile part? (Or, does it have one?) The can seems very expensive for storing it, which often indicates that something will evaporate. I think I read on the last one "use all at once", or something like that. It stores OK in a sealed glass (jelly) jar, but I haven't tried wetting the seal to see if it dissolves it then.

[Soos]

Soos: did the BG44k-in-a-bucket evaporate? I mean, the volatile part? (Or, does it have one?) The can seems very expensive for storing it, which often indicates that something will evaporate. I think I read on the last one "use all at once", or something like that. It stores OK in a sealed glass (jelly) jar, but I haven't tried wetting the seal to see if it dissolves it then.

we had a lid on it.
I would assume it would evaporate.

the prices I remember paying for BG44K was between 15-20$ per can.


l8r