Is there a way to increase compression on a motor that is running or that has low compression w/ some type of engine cleaner or additive.
NOT A MECHANIC
Thanks

 

lolno.

 

LOL
not even a maybe huh
lol

 

Depends, if the low compression is related to worn rings, you can use "engine restore" and it can help restore your compression to some degree. It is a very temporary solution. Essentially the soft metals in it (Copper, Silver, Lead) that fill in the cylinder walls wears away pretty quickly so you pretty much have to use a can every oil change.

Xado engine treatment is supposed to do the same thing but on a much longer duration (60K miles/100K kilometers) by building a cermet (ceramic metal) using the metal particles in the oil. I've coupled the two with fresh oil so Xado has metal to work with and it appears to be giving me some extra life out of my wife's knocking motor (I did Xado and waited a few days then added the engine restore to put metal back into the oil). Surprisingly after a few weeks of her driving it, the knock is hardly noticeable once warm now (can't hear it in the passenger seat any more). And much much subtler when cold. I might just get a solid year to rebuild my backup motor to swap into her car. Time will tell. And hey 50 bucks was a cheap way to get a years extra time to get my crap together.

These additives only help if the compression loss is due normal ring wear. If you have a valve issue, there is no temporary extra life last resort tricks.

A leak down test will tell you if you can squeeze an extra ounce of life from the motor or if you need to retire/rebuild/swap it soon/immediately.

And of course the best way to increase the compression on a running motor isn't by additives as you probably already know. It's a rebuild.

Cheers.

 

Nope, no reliable way. Low compression means some sort of physical damage. Head gasket "sealant" will only gum up the cooling system making repairs even more complicated (and expensive), and if a ring, ring set, or ring land is damaged, it's metal. It's broken. You don't just magically fix broken metal.

 

You also can have low compression just from normal wear.

The additives I mentioned can give a temporary boost in these cases. Like I mentioned, if it's not just normal wear of the rings and cylinder walls, then there is no temporary buying time with some additive.

Neither additive I mentioned is a gum up sealant like stop leak. I'd never suggest using any sort of stop leak additive. Just gave my buddy a sad shake of the head because he was putting in Lucas engine stop leak to reduce his oil leaks. I told him he was gonna gum up his engine and probably kill it, he didn't seem to mind. Then again his Subaru has seen better days.

If it's broken you can't fix it with a can, if it's just worn, you can get a little extra time and life out of an old motor. Once again, it's only temporary though and not guaranteed.

 

OP - Add car/engine information to your first post. See forum Rules sticky.

 

Kind of depends on your definition of "fix" and also depends on why the compression is low.

 

Yeah "fix" was a bad choice of words. I did clarify with buy a little time though.

I always forget and just answer the questions regardless of what information is provided. Moving to the misc./tech being it's not really car specific but can be quite technical in application and science.

 

You can have different types of compression loss, via the rings, head gasket or through the valves. Don't waste your money on trying different additives. Do a a dry compression test and a wet test. That will help you figure out if its the rings or head.

 

No.

 

Picked up a compression tester soon as it stops raining I'll let you know where the numbers fall.
The car is a 97 Civic Hatch but the question was more general and a "for my information" more than anything.

 

Yeah that was a wonderful experiment
Not worthy of repeat .
cylinder 1 starting from closest to distributor
1= 20
2 = 30
3 & 4 = 40
Now the story goes the previous owner bought another car for winter and the hatch sat. it's present state is how it came to me .
Motor only has about 110 on it

 

I've never seen numbers that low.

 

Yeah after seeing that I didn't think a wet test would make to much of a dif.
What do you think

 

Get a new engine.

 

I saw an LS with 45 just the other day... 1-3 were ~125, then 4 was 45... Guy wanted $400 for just the longblock... lol

 

With any luck you just didn't perform the test correctly.....if those are the real numbers, the odometer may not reflect the actual mileage of the car. If the speed sensor was ever broken or disconnected then the odometer will not move while driving. Also a guy can go out and EASILY replace the entire instrument cluster with a "younger" one from a junkyard or other car (I did) and voila you think your car has fewer miles on it than it actually does. There are no complicated cables or anything to deal with, like in older cars, it's just a couple of basic electrical connectors to unplug. When I realized that I was really disheartened by the potential that many cars off used car lots or being sold by sheister private owners may be showing incorrect mileage. I guess Carfax is the only way to get an idea of what the actual mileage may be.

Or maybe the previous owner just enjoyed beating on his car and running it hard with no oil in it or something. Sucks man sorry to hear that.

 

I've also never seen numbers that low. I'm thinking the test was done incorrectly.




Or there's no rings.

 

The only thing I can say is that there is no way to warm up an engine that's not running so this was a cold/dry test
Any suggestion for a better test technique