whats the ramification of running low compression in one cylinder?

[bob johnson]

other than wanting to have equal compression in all cylinders...what is the downside to just running a motor that has much lower compression in one cylinder than the others??

would that be putting pressure on the crank and bearings possibly making them fail earlier than normal??

I can see tuning for high end might be difficult..

I picked up a PARTS motor that runs but has compression numbers of 125 , 125, 130, 90

the 90 being in the lower port cylinder.

I dont want to go into rebuilding it... i am already into another rebuild at the moment..

it isnt fun... could this motor be run day in day out???

Ill try and decarberize once I get a chance( on a stand) and see if the compression adjusts...but just asking anyway

because if it is really bad to run as is, i might start pulling parts now so they are on the shelf in case the motor I am running now needs a part

thanks

bob

 

[oldcatamount]

Re: whats the ramification of running low compression in one cylinder?

I doubt that weak cylinder will give you any problems. The de-carb will help it. I'd run it like it is and just keep an eye on the plug to that cylinder.