Question concerning compression on 90 LX 1.8L DOHC
 

I recently bought a 90 LX 1.8L DOHC 5 speed. It's actually kind of nice (power everything). It has a little over 140,000 miles on it (the speedo quit working). The problem is, the engine smokes pretty bad until warmed up. I pulled the plugs (oily) but not fouled. I did a compression check on it and got #1 150, #2 125, #3 175, and #4 175. I know that #2 is way out of spec (I also own a 92 Escort GT with the 1.8L DOHC and used the specs in that service manual), but what is good compression? I forgot what I had on the Escort (185,000+miles), but remember it was ok. What's a fresh engines compression on this engine? I don't want to soak much money on the car (re-ring kit $294, rebuilt $520, +machining), so I may go to a heavier oil and use a bunch of restore. Any comments?

Bill


90 Protege LX 1.8L DOHC
92 Escort GT 1.8L DOHC
91 Subaru Loyale 4x4 1.8L
87 Subaru GL 4x4 wagon 1.8L (RIP)
99 Yamaha YZF-R1
88 Yamaha YSR-50
75 Honda Z50A
(can't seem to get a car over 1.8L)

The factory spec is 182 psi. The minimum is 128 psi, and the max differential between cylinders is 28 psi.

Yeah, I know, but again, I'm trying keep it as cheap as possible. If I can put a bandaid on it (i.e. "Restore, heavier weight oil, etc) to keep it from being the James Bond smoke screen to drive it to and from work, I'll do it. If not, it becomes a donor car for my Escort and the rest gets parted out. It does run strong still.

This may be a dumb question, but how do you do a compression check? What is involved in it? I have been using Restore with every other oil change for about 21,000 miles now, ever since some light blue smoke appeared when I first started her up. No problem since, but maybe it would be a good thing to check.

Thanks for any help.

Additionally, with the 1.8L DOHC you want to ground the coil to the block. Also block the throttle wide open while you are cranking the engine. To check rings, after you've checked all cylinders, pour about a tablespoon of oil in each cylinder (one at a time) and check compression again. If they went up (a desent amount), it's a good posibility that the rings are gone or on their way out.

Yeah, that's my next step to take and boy am I hoping it could be that simple. But when I did the oil test, it brought the compression up about 40-60psi each cylinder, so I do think it's the rings. I really wish that I had the leak down tester (I have about everything else). I have to find a shop around here to do it, but I don't have tags, insurance or an inspection on the car yet, so I can't drive it anywhere. I also want to price a junkyard motor so that I don't spend too much fixing this one if thats what I decide to do. Is the Escort GT motor a drop in for this one because the junkyard I get parts from has plenty of GTs. I've only noticed a few differences by looking in the engine bay between the two.

Usually around $20. I paid about that (can't remember) from Sears. Comes with different sized threaded adapters for different sized plug holes. It has a nice long hose to fit in the deep plug wells of the DOHC.

I'm almost sure that my Escort has a return. Another question, are the tranny's the same ratio? If I decide to part it, I may stick the tranny (it's been rebuilt recently) in the Escort. Thanks.

OK.... got a question (hellllllluva old thread), how do you compression check a junkyard motor? How do you hand crank it? :)