Garage Storage Organization and Garage Cabinets

BUBBA · **Compression test...results & ideas**

I did a compression test today to see how things are. got 120-120-100-95. Poured a bit of oil in number 3&4 cylinders and compression came up so my rings are ready to be replaced after only 6k miles. Everything runs good so I'm just gonna replace the rings. I'm thinking about going with the sealed power rings. Anything I need to know about these? Are they file-fit? This is on a 2.5 motor. When I had the motor re-built before I just had the cylinders surface honed. I may even put in a crank scraper. I've never changed out the rings with the motor still the car, but I know a lot of people have, so I guess it shouldn't be all that hard. I may even take this chance to have my head re-built and put in some head studs and cometic head gasket. Any suggestions on all of this? Thanks.

Christian J. Grest

LancerShelby · 01-18-2004, 11:20 AM

Rings sound like a good idea, but just use the Mopar stuff for gasket and head bolts, no one has had problems with either, that warrants using better stuff.

BUBBA · 01-18-2004, 11:23 AM

Now I just wonder what my chances are of being able to slap new rings in without having to surface hone the cylinders again? I'm kinda scared of doing that with the motor in the car because of all the little shavings.

Christian J. Grest

BUBBA · 01-18-2004, 01:13 PM

Could it possibly be that the headgasket is starting to leak? Just kinda funny that the compression is lower on number 3 and 4 cylinders, but the other 2 cylinders are fine. I had heard stories about 2.5 motors lifting headgaskets when running over 20psi of boost on reguler headgaskets and head-bolts. Thanks.

Christian J. Grest

iTurbo · 01-18-2004, 01:27 PM

You'll know as soon as you pull the head....I'd check the exhaust valves for burnt edges too.

need4boost · **newbie advice**

Well, I'm new to turbo dodges, (as in I'll be picking mine up this week), but not new to engines. I test them for a living, and I have to say, do not install new rings without at least running a ball hone through the cylinders. they will not seal up properly, if at all. You definitley need to break the glaze. Hope you haven't already installed them. Just my two cents worth.

Chris

LancerShelby · 11:21 PM

I could be cracked pistons, which in fact would be a better thing since you most likely wouldn't have to put in new rings

I had 2 cracked ones in my motor from last year, and my compression on the worst one was 75 and the other was 110.

Oh and seriously, if you run an MP gasket and mopar head bolts, you will have no problems. I have in all my cars with absolutely no problems, and with one of them I didn't even prep the block and head surfaces properly, just slid the old one out, ran a rag between the 2 and slid the new one in

BUBBA · 02-09-2004, 12:15 AM

Well, I redid the compression test a few weeks back when the motor was cold and got 125 across all 4 cylinders. The reason I did it this way is because I was thinking that maybe some fuel left over in 3 & 4 caused the readings to be lower. I went ahead and got the thick cometic head gasket and ARP head studs from Cindy at FWD Perf. I'm toying with the idea of just holding off till I can save up the money for some forged pistons.

Christian J. Grest

ebola · 02-09-2004, 05:06 AM

I wouldnt trust oil test much. Oil seals valves too. First take off head, check pistons for wear, valves for play in guides. ..then take a decisions. Rings are often blamed for leak without proper check, but after appears there are more problems with valve seats or cylinder/piston wear.

BUBBA · 02-09-2004, 06:55 AM

I plan on having the head gone over when it's off this time, something I have yet to do on this "junkyard head".

Christian J. Grest

**mopar2ya** · 02-11-2004, 02:19 AM

If you poured a little oil in the low cylinder and it came up, its rings. You should be ok to just stick rings in unless the cylinder is messed up. After all something caused that cylinder to be low.

walalce

turbovanman · 02-11-2004, 09:14 PM

And don't forget to hone the cylinders otherwise the rings will never seat. Use a ball hone, the old 3 finger units don't work as well on smaller engines, I learned the hard way. Rerung a Fox and the rings never seated. Pulled apart, new rings and a ball hone and no more problems. Thank god you can do them in the car easily, "thumbs up

LancerShelby · 02-12-2004, 12:23 AM

Quote:

Originally posted by turbovanman
Use a ball hone, the old 3 finger units don't work as well on smaller engines, I learned the hard way.

Well I guess all the local engine shops should change their method?

turbovanman · 01:09 PM

Quote:

Originally posted by LancerShelby
Well I guess all the local engine shops should change their method?

Well I guess that when I rering in the car, I will hook up the machines they have to get a perfect hone. I didn't realize that older engines don't have perfectly round bores and the best way to get a good hone is to use a ball hone! Silly me, what was I thinking.