I have a 1973 f engine with very low compression thinking of looking into a gm straight 6 or v8 I have a 3 speed on the tree with vacuum on original chassis and also have a 4sp from on a 1973 chassis at this point looking for cheapest option to get on the road and ls swap down the road. Would love to get another straight six or v6 or v8 thanks happy holidays
1f no compression looking for options (1 Viewer)
- Thread starter Dave54000
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- 1f compression looking options
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Skreddy
SILVER Star
Is it low across all cylinders? What are the numbers? How does it run?
So what are the dry and wet compression #'s? Maybe just a valve job to limp by. Maybe knurling the pistons and new rings in a scuffed up bore. Changing motors and stuff. I'd want more gears, a super low and a really good overdrive or 2.
pb4ugo
SILVER Star
I think the 3 speed bellhousing adapter is probably the cheapest. I think it bolts to the stk bellhousing. Im not really familiar with it. The 4 speed requires a conversion bellhousing. The 4 speed is more refined.
You could use a GM tranny the adapt to a stk 1 piece tcase or split tcase. Or maybe use a 5 speed. Or something not related to Toyota. All require driveshaft mods, exhaust, and motor mounts etc. The small bits to finish the conversion will nickle and dime you once the big stuff is installed. A 73 40 didn't come with a 4 speed. What's your plans with your 40? Street, trail etc...
You could use a GM tranny the adapt to a stk 1 piece tcase or split tcase. Or maybe use a 5 speed. Or something not related to Toyota. All require driveshaft mods, exhaust, and motor mounts etc. The small bits to finish the conversion will nickle and dime you once the big stuff is installed. A 73 40 didn't come with a 4 speed. What's your plans with your 40? Street, trail etc...
- Thread starter
- #5
Engine does not run been in storage for long time supposedly was turned over every now and then for compression only one cylinder got 90 lbs the rest 60 and 30 and one with none might try another gauge
stuck valves? squirt oil through the spark plug openings? cranking speed? open air path through intake manifold?
If you want "useful" advice here, you'd better state your budget. More gears, overdrive, engine, transmission, driveshaft changes, adapters, etc. etc.
If you want "useful" advice here, you'd better state your budget. More gears, overdrive, engine, transmission, driveshaft changes, adapters, etc. etc.
If you need a rebuilt head.
I have a fresh one here in Florida.
I have a fresh one here in Florida.
- Thread starter
- #8
- Thread starter
- #9
First thing I did was pull spark plugs and look in cylinders looked like some s*** on top of pistons vacuumed out and oiled cylinders thru spark plug holes then pulled valve covers and crank engine over with starter saw one stuck valve freed it up with some spray and oil and with a little help freed up. Then I removed dizzy and primed the oil pump with drill did get good oil pressure something like 40 to 50 lbs then did compression ck all plugs out and carb open and closed didn't matter low compression tried for a minute to start just a couple back fires oil up cylinders and called it a day.
- Thread starter
- #10
Pull the plugs out check/set the valve lash. The do the dry/wet compression test. I like the screw in the spark plug adapter tester units. Got one from Amoron for like $30 that works great. You might also look in the bores with a scope - Amoron has some good prices on them too. A second compression a few days later might be a good idea, after the Marvel's Mystery oil has a chance to work on the rings. If you can then get it running, beating on the valves might help clear the seats.
- Thread starter
- #12
My plan was to get the 1.5f running that is on a painted frame 4sp and front disk brakes and put 70 body on it. Then clean up 70 frame. But now I am thinking to just get the the 70 body and frame running and driving its 3 on the tree and 4 wheel drum brakes so if I can find a decent engine get that going with either 3 on tree or 3 or 4 on floor not excited about vacuum system the fj40 will mostly used around town and rare light trail logging roads
- Thread starter
- #13
Plan getting another compression tester maybe it was bad don't know where it got it
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- Thread starter
- #14
If I can't save the f1.5 leaning toward a gm straight 6
pb4ugo
SILVER Star
Sounds like the engine has been sitting for a while, you may get better compression #'s if you run it for a while. Gm 6's are pretty old too.
This is just my taste in power plants but if I were in your situation I would find a rebuildable Chevy 292 straight six to drop in. Big sixes of that displacement have great torque numbers and overall power and are simple to work on
Skreddy
SILVER Star
When you got the distributor back in, are you sure it isn’t 180 out?
Have you touched the carb or points? Basically: are you sure you have good spark and you’re getting fuel? Is it good fuel?
My personal preference, but if I went away from an F series engine (F, 2F), I’d go to a small block Chevy, a 4.3L Chevy or small block ford. Why spend the same time, money and effort to not get any more performance?
Post some pics of the engine bay to show what you’re working with.
- Thread starter
- #18
I soaked the rings and got new compression test still extremely low compression 90, 3-60 a 30 and a zero reading I tried with carb open and closed and plugged vacuum ports on carb and manifold only else that wasn't hooked up coolant system. Only thing left to try I guess is pull head and inspect and try new head gasket
pb4ugo
SILVER Star
If you didn't see a significant increase in compression by squirting oil in the cylinder your testing, then it's most likely a problem in the head.
- Thread starter
- #20
Ok thanks
