20R - Coolant in oil; Head Gasket gone - advice?

[yotadude520]

Morning mudders!

I've got a 1980 Pickup with the 20R motor and on Saturday I drove it (Didn't go far, maybe a mile away) About halfway back to my house I noticed it had completely lost power. Couldn't get it to go above 35 mph in third gear and I limped it home. Once I got home I noticed there was coolant in the oil. I'm pretty sure the head gasket has gone on it. It has a new water pump and the radiator was full of coolant when I checked it after it cooled down. The temp gauge is also pinned to H, even when the motor was cold so I'm thinking the sending unit is toast.

So, I have a couple options. I'm thinking about just replacing the HG and getting it back on the road again. I'm worried however if there was any collateral damage done to the head and I'm pretty sure I'd have to get it looked at.

The second option is to go ahead and put in a new motor. My buddy Danny has got a 22R that was professionally rebuilt but the kid who owned it forgot to put oil in it and spun a bearing. He's already got the crank out and has verified that is the only issue with the motor. So it would need new bearings, and I'd have to get the crankshaft turned but I'm thinking if that's it, the truck would have a really nice reliable motor as that one only has got 20k on it. I was able to even talk him into trading it to me for some old axle parts I have lying around so it'd be a pretty cheap fix. Really considering this one since the 20R might be on borrowed time.

Here comes the third option. I could also take the head off of the 20R and put it on the 22R block (as long as the head isn't damaged)

I'm not sure what I'm going to do. I may decide to do all three. (Fix the HG, get the motor and tinker on it, maybe get another 20R head and put it on and just build it).

What do you guys think I should do? Any and all advice is much appreciated.

 

[steffan]

What’s your budget? Around here you can get a completely rebuilt 22r for $1k.... I’d look for a rebuilt before piecing together a bunch of worn out/ broken parts? On the other hand, if your looking for a project, just tear down the engine and see what’s wrong - might not be so bad

 

[yotadude520]

What’s your budget? Around here you can get a completely rebuilt 22r for $1k.... I’d look for a rebuilt before piecing together a bunch of worn out/ broken parts? On the other hand, if your looking for a project, just tear down the engine and see what’s wrong - might not be so bad

Right now my budget isn't too high, definitely not a grand! Somewhere around $500 would be good with me. The truck is a toy so it's not a high priority, but it's already killing me to see it just sitting in the yard.

If it was any other car, I would probably just tear down the motor that's in it but it's always been my plan to go with a 22R or 22RE in that truck. Plus the 20R that is in it was a junkyard motor with unknown mileage that was put in back in 1997 (actually ripped out of a 70's Corona). I know the 22R that Danny has got is in pretty good shape so I'm thinking if I just rebuild the bottom end (new bearings, crankshaft, new rods and piston rings) it'd be pretty reliable for me. I can get a pretty decent rebuild kit for $350 and then just get the crankshaft turned or buy a new one for another couple hundred.

But I'm also heavily considering just building that 22R with a 20r head and making the hybrid so that I could swap over alot of the parts already on the truck like the intake manifold, carb and exhaust. It's something I've never done before so it could make for a fun build.

Thoughts?

By the way truck in question pictured below:

 

[Gumby]

I think I would go with the 22R. I'd be surprised if a good crankshaft for one would cost a lot more than having one ground.

 

[H8PVMNT]

I would do a budget rebuild but do the hybrid. They work well and definitely make a bit more power. The 20r crank will work in the 22r too, if it helps. If you don't have too much taper in the journals you can polish them with a shoelace, emery cloth and WD40. Still turning down a crank is not too much money. I just did a budget rebuild on a 20r and ended up right around $500 even after machine work on the block. I am trying a regular 20r with a healthy cam this time to see if the head is the real difference or the added compression from the 22r bottom end... Annoying Orange, 20r Build for the 1980 Pickup

With clever use of resources and a little ingenuity it can be done.

Cool pickup.

 

[yotadude520]

I think I would go with the 22R. I'd be surprised if a good crankshaft for one would cost a lot more than having one ground.

That's exactly what I'm thinking. It'd be a nice upgrade for sure.

I would do a budget rebuild but do the hybrid. They work well and definitely make a bit more power. The 20r crank will work in the 22r too, if it helps. If you don't have too much taper in the journals you can polish them with a shoelace, emery cloth and WD40. Still turning down a crank is not too much money. I just did a budget rebuild on a 20r and ended up right around $500 even after machine work on the block. I am trying a regular 20r with a healthy cam this time to see if the head is the real difference or the added compression from the 22r bottom end... Annoying Orange, 20r Build for the 1980 Pickup

With clever use of resources and a little ingenuity it can be done.

Cool pickup.

Thank you very much H8PVMNT for the rebuild thread! And that definitely helps. Like I said I'm not sure of the state of my current 20R but I'd really like to do the Hybrid. Gives me a fun little project to work on and also will be a huge power increase for the ol' Yota. Now when doing the hybrid build would you reccomend I rebuild my 20R head? I can see doing it for some insurance since I'm a little worried the increased compression could cause problems. What mods would you do to the head if you were to do this swap? I've read that people have put bigger valves in it. Or should I just throw my head on and call it a day?

Never done this build before so any and all info is much appreciated! Thanks by the way! It's a fun little trail rig with the battle scars to prove it's capable haha.

 

[H8PVMNT]

Well the bigger valves they use are usually just the 22r valves. The issue is that they are just a bit shorter which limits the amount of lift you can use. I was considering using them but after talking to Tim at DOA I am convinced for a mild build the velocity offered by the smaller valve and the shrouding effect of the bigger valve would make it a wash.

I would take your valve seals off and push side to side on your valve stems. If there is much wiggle at all I would try to do fresh 20r valves and valve guides. They can be had really cheaply and are pretty easy to do at home. I think the DNJ valve guides were only like $1.62 each. I think I have the valve guide removal/installation in my thread some place.

All I would do other than that is a gasket match of the intake and exhaust ports and drill the brass looking air injection tubes out of the exhaust side.

Not saying you can't use the head as is but when you have it apart that's your chance to freshen things up and the port matching doesn't cost any more than a cheap dremel. Whatever you decide to do the hybrid is definitely a good setup. I could pull on a 3RZ swapped rig with my 4runner last summer with mine and it was stock 20r head with a stock cam and a weber.

 

[yotadude520]

Well the bigger valves they use are usually just the 22r valves. The issue is that they are just a bit shorter which limits the amount of lift you can use. I was considering using them but after talking to Tim at DOA I am convinced for a mild build the velocity offered by the smaller valve and the shrouding effect of the bigger valve would make it a wash.

I would take your valve seals off and push side to side on your valve stems. If there is much wiggle at all I would try to do fresh 20r valves and valve guides. They can be had really cheaply and are pretty easy to do at home. I think the DNJ valve guides were only like $1.62 each. I think I have the valve guide removal/installation in my thread some place.

All I would do other than that is a gasket match of the intake and exhaust ports and drill the brass looking air injection tubes out of the exhaust side.

Not saying you can't use the head as is but when you have it apart that's your chance to freshen things up and the port matching doesn't cost any more than a cheap dremel. Whatever you decide to do the hybrid is definitely a good setup. I could pull on a 3RZ swapped rig with my 4runner last summer with mine and it was stock 20r head with a stock cam and a weber.

Thanks for all the feedback! I'm going to still do the 22R/20R build but I did go ahead and replace the head gasket yesterday, and....

IT RUNS!! She's back to life and ready to hit some trails!

Thanks everybody for all your input. I'll be keeping progress on how the build goes!