Until I get all the items I need to do my Turbo 2.3/T-5 swap I'm trying to get my '73, 2000 serviceable. My car was advertised as "running on three cylinders." I found that the valves had likely never been adjusted and the cam was showing wear marks on the heel.
I reset the valves about 20% looser than stock (.010 / .013) in the hopes of knocking some probably carbon off the seats and it seemed to help. The readings went from/to:
Before #1 - 110, #2 - 50, #3 - 130, #4 - 140
After #1 - 110, #2 - 130, #3 - 130, #4 - 140
I immediately checked the compression after the valve adjustment and there was no change. However, after 75 miles of driving the #2 cylinder went from 50 to 130! Yea, I know #1 at 110 is getting down there, but the motor is only temporary.
Anyway, curiosity is getting the best of me. In looking in three manuals I found nothing as to the actual reading values. All three manuals stated, "cylinders should be within 75% of each other." Does anyone know off hand what the readings measureable range should be (in PSI not percentage of each other).
Thanks, Tom
Wittsend,
I read your post and immediatly looked into my books.....but then I thought back and can't remember if I have ever seen a compression specification in any manual. But if my memory serves me well 100 is good and anything above that is excellant. If you getting 140 ...that is killer. The magic number needed to calculate your compression is the Head volume...the deck height can be estimated and the gasket thickness also. The stock compression for your car as per the 1977 Motor manual says 8.2....What???? And the 75 percent differential in compression has to be a typo....It should be 25% That is like saying 100 psi to 25 psi....duh. I might suggest to you to do a wet comp check ( if that is not what you already have done) and see if the levels even out a little closer. Did you say that car sat for 16 years?? If it did you are doing good.
High_Horse
H_H,
Now that you mention it, that is a strange way of saying it. You are right though they mean no more than 25% difference between cylinders.
Yea, the car was proported to have sat for 12 years. The power seems acceptable on level ground, but going up even small inclines with the automatic it labors. My 19991 mazda 323 seems to have twice the power from a 1600 and a 5-speed. That Mazda motor also has twice the mileage of the Pinto (165,000 - vs - 86,000). I guess until I do the 2.3 Turbo/T-5 swap I'll just have to live with the liesurely pace of a 1970's smog motor, auto. trans. car.
Tom
The H P Books titled "how to rebuild your 1.3, 1.6, & 2.0 OHC FORD" by David Vizard (ISBN: 0-912656-68-9) has three different listings for the 2.0 based on compression ratio as follows:
ratio 8.2 pressure 128-157psi
ratio 8.6 pressure 136-165psi
ratio 9.2 pressure 157-184psi
I believe the 71 had a 9 something ratio while the later 2.0's had a ratio in the 8's. The book mentions that pressures 20-30psi under the above may mean something is amiss.
Thank you Jerry.
Those numbers tell me three cylinders are in range and one slightly out. Frankly the motor is only temporary, but on a hill it really seems labored. I'll attribute 33% to the engine condition, 33% to the 1970's smog choked design and 33% to the auto trans.
Tom
oldkayaker,
Thumbs up on that. What book is that H.P.????
High_Horse
Yes! The automatic transmission just KILLS these cars! I have two 4 spd pintos and one Automatic pinto and both of the 4 spd one will leave the auto one in the dust. All three are 2.3L powered, and one has a higher ratio than the auto and the other has a lower ratio than the auto.
High Horse,
HPBooks, Inc. is a publisher that put out many auto related books. They were and may still be at P.O. Box 5367, Tucson, AZ 85703, 602-888-2150.