Help! Bought 1985 22r pickup with seized engine, now very low compression readings
04-11-2017, 02:06 PM
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Help! Bought 1985 22r pickup with seized engine, now very low compression readings
Hello Yotatech,
I am going to warn you before hand that this will be a lengthy post. First off, about 2 months ago I bought a 1985 Toyota Pickup 4x4 with 140,000k miles from my roommate’s dad who bought the pickup new in 1985. It was non-running when I bought it, but it had been sitting inside of a quonset, out of the elements, for nearly 20 years as the plates date back to 1998. When I talked to my roommate's dad, he said he had parked it because one day it started running roughly because of the timing. He also commented he never had any of the timing components replaced. He also commented he got it running again in the early 2000's.
So when I got it, I discovered that the engine was seized. With the help of a friend rocking the truck back and forth in 5th gear, we were able to free the engine enough that it would turn over manually by the crank bolt about 90 degrees, but not enough to hit TDC. At this point I was worried that by rocking the truck back and forth while in gear would break something (like a valve since I thought it was out of time according to PO).
At this point, with the engine only turning 90 degrees, I went ahead and purchased Ted at engine builders timing chain kit with new chain, tensioner and guides. When I took everything apart, surprisingly all guides, passenger and driver, along with the chain and tensioner were still intact and not broken but of course original. After I took the old timing chain off I made a real rookie mistake. With the bottom end still locked up, I went ahead and manually rotated the cam gear to see if anything was binding in the top end of the motor. Quickly I learned nothing was binding in the top end. After rotating the cam gear a full turn I knew the bottom end was what was stuck. So with the chain off (I don't remember what position the cam was in), the roommate and I began pushing the pickup back and forth in gear until the bottom end broke loose. Hopefully no valves were bent in doing this but I'm not convinced.
Once we broke it loose, I lined everything back up at TDC and put the new timing chain components on and sealed everything up. Once everything was back together I rented a compression tester and tried manually getting compression readings by turning the crank bolt. I couldn't get any readings this way. So I filled the engine up with oil, hooked up a battery, and cranked the sucker over by the starter. It worked!!! Here are my compression readings for each cylinder:
#1 - 30 psi
#2 - 60 psi
#3 - 0 psi (yes 0 psi)
#4 - 60 psi
Not good. And that's where I'm at. I basically have an engine that I don't know why I'm getting low compression--other than the bent valve scenario from before. I am fighting tooth and nail against pulling the head because I truly believe I’m missing something here. My next plan of action is to rent a leak down tester to see where I'm getting blow-by.
If all else fails would you recommend pulling the head or just give up and start looking for a used engine. I want to buy a used engine because A) IF I can find one it will be cheaper than a re-man and B) I don’t want to spend the money on a re-man because I don’t know if the rest of the truck is even worth a damn. It might need a bunch of other things to get it road worthy. I just want to drive this sucker.
If any of you have any suggestions on what to do or if I’m missing anything please let me know
I am going to warn you before hand that this will be a lengthy post. First off, about 2 months ago I bought a 1985 Toyota Pickup 4x4 with 140,000k miles from my roommate’s dad who bought the pickup new in 1985. It was non-running when I bought it, but it had been sitting inside of a quonset, out of the elements, for nearly 20 years as the plates date back to 1998. When I talked to my roommate's dad, he said he had parked it because one day it started running roughly because of the timing. He also commented he never had any of the timing components replaced. He also commented he got it running again in the early 2000's.
So when I got it, I discovered that the engine was seized. With the help of a friend rocking the truck back and forth in 5th gear, we were able to free the engine enough that it would turn over manually by the crank bolt about 90 degrees, but not enough to hit TDC. At this point I was worried that by rocking the truck back and forth while in gear would break something (like a valve since I thought it was out of time according to PO).
At this point, with the engine only turning 90 degrees, I went ahead and purchased Ted at engine builders timing chain kit with new chain, tensioner and guides. When I took everything apart, surprisingly all guides, passenger and driver, along with the chain and tensioner were still intact and not broken but of course original. After I took the old timing chain off I made a real rookie mistake. With the bottom end still locked up, I went ahead and manually rotated the cam gear to see if anything was binding in the top end of the motor. Quickly I learned nothing was binding in the top end. After rotating the cam gear a full turn I knew the bottom end was what was stuck. So with the chain off (I don't remember what position the cam was in), the roommate and I began pushing the pickup back and forth in gear until the bottom end broke loose. Hopefully no valves were bent in doing this but I'm not convinced.
Once we broke it loose, I lined everything back up at TDC and put the new timing chain components on and sealed everything up. Once everything was back together I rented a compression tester and tried manually getting compression readings by turning the crank bolt. I couldn't get any readings this way. So I filled the engine up with oil, hooked up a battery, and cranked the sucker over by the starter. It worked!!! Here are my compression readings for each cylinder:
#1 - 30 psi
#2 - 60 psi
#3 - 0 psi (yes 0 psi)
#4 - 60 psi
Not good. And that's where I'm at. I basically have an engine that I don't know why I'm getting low compression--other than the bent valve scenario from before. I am fighting tooth and nail against pulling the head because I truly believe I’m missing something here. My next plan of action is to rent a leak down tester to see where I'm getting blow-by.
If all else fails would you recommend pulling the head or just give up and start looking for a used engine. I want to buy a used engine because A) IF I can find one it will be cheaper than a re-man and B) I don’t want to spend the money on a re-man because I don’t know if the rest of the truck is even worth a damn. It might need a bunch of other things to get it road worthy. I just want to drive this sucker.
If any of you have any suggestions on what to do or if I’m missing anything please let me know
