DeCarbing Was A Bad Thing???

[Boss Hawg]

As i said in a earlier thread i checked the compression on my 1987 70hsp Johnson & the 3 clyinders varied from 135 - 150 -
I just checked again after a fairly goog decarb job & all 3 dropped compression but now all 3 are at almost exactly 120
Is this good or bad???

 

[iwombat]

Re: DeCarbing Was A Bad Thing???

Could very well be you removed some big carbon deposits from the top of the pistons, or the inside of the heads and lowered the compression a bit. Yep, that's a good thing.

 

[Boss Hawg]

Re: DeCarbing Was A Bad Thing???

Could very well be you removed some big carbon deposits from the top of the pistons, or the inside of the heads and lowered the compression a bit. Yep, that's a good thing.

Whew-- I was sure hoping so
Thank you for easing my mind quickly!!!!

 

[bob johnson]

Re: DeCarbing Was A Bad Thing???

I just popped the heads off my 1988 70 ...and whuile I have had a previous problem which left me with shrapnel embedded in the head and the top of the piston..there was only a little carbon on the piston tops in the two cylinders with out the issue... and almost none on the piston with the shrapnel...

all three chambers of the head were as clean as a whistle...ZERO carb....

zilch...

is this common?

where else does the carbon build up , that needs the benefit of a decarb???


down the intake at all??

down the exhaust?

THE CARBONIZATION is only the result of burnt oil-gas???

thanks

bob

 

[JB]

Re: DeCarbing Was A Bad Thing???

Bob, you need to start a new thread with a new question. Hijacking is bad manners.

 

[bob johnson]

Re: DeCarbing Was A Bad Thing???

I was going to later on today...but when i read about the carbon that guys say builds up on the piston and cylinder..i thought it was a perfect time to post a cylinder with no carbon.... and ask the question.

my thinking was guys who know about that stuff and who were already in on the thread could easily reply.

I'll try to behave better from now on....

I still have a lot of work ahead of me on the 70HP

bob

 

[Boss Hawg]

Re: DeCarbing Was A Bad Thing???

Thanks JB
Bob, no harm, we all want to get our stuff going right

 

[bob johnson]

Re: DeCarbing Was A Bad Thing???

Thanks JB
Bob, no harm, we all want to get our stuff going right

so you wanna trade motors right now straight up????( there is room to twist my arm tomorrow) ha ha

ps all the paintable parts are all redone and ready to bolt on!!! and you get a whole year newer motor ha ha

bob

 

[Boss Hawg]

Re: DeCarbing Was A Bad Thing???

so you wanna trade motors right now straight up????( there is room to twist my arm tomorrow) ha ha

ps all the paintable parts are all redone and ready to bolt on!!! and you get a whole year newer motor ha ha

bob

Well------Yours is a whole year newer
Best of luck my freind ---

 

[coolguy147]

Re: DeCarbing Was A Bad Thing???

alright... enough boning and sorrys for the other person


well u rather have a motor 100psi and above and like dead even then haveing a motor have 120 in a cylinder then 150 then 110. ur mainly looking for evenness

 

[tashasdaddy]

Re: DeCarbing Was A Bad Thing???

carbon also builds up around the rings, and can sieze them, decarbing is alike an enema when you are distressed. it gets all the old crud out of the engine. and cleans the exhaust.

 

[Boss Hawg]

Re: DeCarbing Was A Bad Thing???

carbon also builds up around the rings, and can sieze them, decarbing is alike an enema when you are distressed. it gets all the old crud out of the engine. and cleans the exhaust.

That puts it into perspective
I was concerned on the first since it had dropped & double checked
The middle was the same & i was courious
The last was exactly the same & i thought it was great
Took me bout 3 minutes to get to my computer to ask ya'll to be sure
Thanks again for all the great info i've gathered here!!