Compression test
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From: King George VA
Compression test
Just performed a Engine Cleaning and Compression test on my 1969 F-100 with the following results:
Cyl - Reading
1 - 120
2 - 120
3 - 122
4 - 120
5 - 100
6 - 115
7 - 122
8 - 100
These were completely dry so I think the readings are very good for a 30 year old engine with no docs and unknown mileage.
After spraying Gunk all over the engine and waiting the requisite 15 - 20 minutes, I hosed it off. I made sure to cover the Distrib and the carb with aluminum foil. I somehow ended up with water in the oil.
Any suggestions as to how the water got in there? Any comments on the compression test?
Thanks
Cyl - Reading
1 - 120
2 - 120
3 - 122
4 - 120
5 - 100
6 - 115
7 - 122
8 - 100
These were completely dry so I think the readings are very good for a 30 year old engine with no docs and unknown mileage.
After spraying Gunk all over the engine and waiting the requisite 15 - 20 minutes, I hosed it off. I made sure to cover the Distrib and the carb with aluminum foil. I somehow ended up with water in the oil.
Any suggestions as to how the water got in there? Any comments on the compression test?
Thanks
Last edited by povphile; Aug 31, 2003 at 10:46 PM.
Post Fiend
Joined: Jun 2003
Posts: 8,209
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From: Black Hills of SD
Compression test
A general rule of thumb on compression is no more than 10% variation between the highest and lowest cylinders. 100 is a bit low but I have seen worse. I had a 59 chevy belair with a 283 that had 100 in every hole indicating a good bit of internal wear. I drove the car about 20,000 miles and gave it to my sister for a wedding present in 91. Her oldest boy drove it all through high school until he graduated last year and drove it pretty hard. It still runs as good as it did when I got it. One good thing about it was that it cranked over easy. We had a bad storm one christmas and at 28 below it was the only car I had that would start right up without being plugged in.
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From: King George VA
Compression test
Originally posted by willowbilly3
A general rule of thumb on compression is no more than 10% variation between the highest and lowest cylinders. 100 is a bit low but I have seen worse. I had a 59 chevy belair with a 283 that had 100 in every hole indicating a good bit of internal wear. I drove the car about 20,000 miles and gave it to my sister for a wedding present in 91. Her oldest boy drove it all through high school until he graduated last year and drove it pretty hard. It still runs as good as it did when I got it. One good thing about it was that it cranked over easy. We had a bad storm one christmas and at 28 below it was the only car I had that would start right up without being plugged in.
A general rule of thumb on compression is no more than 10% variation between the highest and lowest cylinders. 100 is a bit low but I have seen worse. I had a 59 chevy belair with a 283 that had 100 in every hole indicating a good bit of internal wear. I drove the car about 20,000 miles and gave it to my sister for a wedding present in 91. Her oldest boy drove it all through high school until he graduated last year and drove it pretty hard. It still runs as good as it did when I got it. One good thing about it was that it cranked over easy. We had a bad storm one christmas and at 28 below it was the only car I had that would start right up without being plugged in.
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From: Texas Hill Country
Compression test
Originally posted by povphile
I made sure to cover the Distrib and the carb with aluminum foil. I somehow ended up with water in the oil. Any suggestions as to how the water got in there? Thanks
I made sure to cover the Distrib and the carb with aluminum foil. I somehow ended up with water in the oil. Any suggestions as to how the water got in there? Thanks
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From: Thomson, GA
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From: King George VA
Compression test
Thanks Guys. I am going to regasket the top end and front. I dont want to pull the engine just now so I will wait on the oil pan. While I have the heads off I will Prob put on new springs, and lap the valves in.
I am also going to do the rear main while i am replacing the clutch....
Sounds like I shopuld just go ahead and pull the stupid thing and do it right!
Oh Honey.....
I am also going to do the rear main while i am replacing the clutch....
Sounds like I shopuld just go ahead and pull the stupid thing and do it right!
Oh Honey.....
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From: california
Compression test
A word of caution if you're going to do a valve job only. It can create blowby because now your top end is better sealed and holds more pressure, but your rings and cylinders are still worn.
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From: King George VA
Compression test
Thanks for the tip. Got the hoist and stand on the way. Just gonna do it all. Rings, Reseat the valves, gaskets, complete inspect and replace if necessary, HV oil pump etc.
Anything obvious to you guys I should keep an eye out for. I Beleive it is the 360 that came with the truck which is a camper special.
Thanks again
Anything obvious to you guys I should keep an eye out for. I Beleive it is the 360 that came with the truck which is a camper special.
Thanks again
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From: Texas Hill Country
Compression test
Not clear if you are re-seating the valves yourself, or sending the heads out... either way, be sure to use hardened seats. Unleaded gas, ya know. Good choice on the HV oil pump, may want to look at a HV water pump as well.
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From: King George VA
Compression test
Originally posted by GolferSA
Not clear if you are re-seating the valves yourself, or sending the heads out... either way, be sure to use hardened seats. Unleaded gas, ya know. Good choice on the HV oil pump, may want to look at a HV water pump as well.
Not clear if you are re-seating the valves yourself, or sending the heads out... either way, be sure to use hardened seats. Unleaded gas, ya know. Good choice on the HV oil pump, may want to look at a HV water pump as well.
Was looking for an HV waterpump. The other thing i seem to have trouble locating is a set of headers. Seems easy to find for the 4wd but not so much for the 2.
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From: King George VA
Compression test
Originally posted by Faithful Old Road Dog
If you're going through the whole engine, you may want to inquire about costs of boring the cylinders and longer rods to make it a 390.
If you're going through the whole engine, you may want to inquire about costs of boring the cylinders and longer rods to make it a 390.
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Joined: Apr 2002
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From: Texas Hill Country
Compression test
My bad... I meant hardened valve guides, of course.
High volume water pumps
http://www.stewartcomponents.com/htm...ord/stage1.asp
Ford truck headers
http://www.team-performance.com/part...ckup%20F%2D100
Good luck with your project!
High volume water pumps
http://www.stewartcomponents.com/htm...ord/stage1.asp
Ford truck headers
http://www.team-performance.com/part...ckup%20F%2D100
Good luck with your project!