My 77 620 K/C 4x4 project.

[RacnJsn95]

Well, came home after work pulled the pan... Turning the engine over there was a noticable tight spot. Here are our suspects:

 

 

You can see the rod (caps) on 2 & 3 got pretty hot, so naturally I pulled them off first to check out the situation... As I suspected both were spun, although it wasn't as impressive as the last one. Pulled off 1 & 4 and they looked ok:

 

Laid out in line 1, 2, 3, 4

 

The crank doesn't look even close to as bad as it was last time. Although the top side of the #2 journal has a noticable hot spot. Interestingly, the back side of the #1 & 4 rod bearings look like this:

 

 

Showed it to my Dad, and he suspects it's because I didn't have the rods resized when I first put the engine together... Guess I should have checked the clearances with the plasti-gage the first time, and I would have caught it before anything ever happened...

 

I dont really want to pull this engine back out, just to put it back in again when I plan on dumping in an LZ22 anyway. My dad suggests taking the Z22, put new bearings in it, and rings, after a quick hone job, then use the L20b top end on it. A "quickie" rebuild; which could be possible before hunting season... Save the L20b short block for a turbo project or something.

[datzenmike]

You know ... I don't think those two rods are getting any oil.

 

Are the numbers on the caps matched to the numbers on the rods?

 

With the cap off run a pipe cleaner up the oil feed in the crank journal. The #2 will go up towards the front and #3 will go up to the back. Any blockage? you should be able to poke in there 6 or more inches.

[lynchfourtwenty]

i've seen that happen if the bearings or caps get put in backwards.. the oil passage doesnt line up so they gets no oil.. but im sure you didnt do that..

[datzenmike]

On a main bearing yes. The oil comes down through an internal gallery to the back of the top bearing half. If it is in wrong and the hole in the bearing does not line up ... no oil. On a rod the oil comes out of the crank that is cross drilled back to the main bearing.

[lynchfourtwenty]

ya something like that..:P

[RacnJsn95]

Yup, numbered caps are matched to the rods; caps on the right way; bearings not backward or upside down... I'll try the pipe cleaner trick after I get the engine out later this month...

 

Rather than try a band-aid fix again, I'm leaning towards something else... Not sure how I should go about it yet though... I bought a 79 620 k/c today for $50 (I mentioned it a couple pages back months ago)... With the exception of the fenders everything on the truck is in way better shape than mine. Plus it appears to have a complete (what appears to be) factory a/c setup:

 

 

The compressor is mounted on the pass. side above the alternator, as mentioned in other topics on factory a/c. The compressor isn't locked up so that's a good sign...

 

With this other truck being in much better shape than mine I'm either

A: Going to put the bed, cab, hood, and everything else good on my current 620... -or-

B: Take my 4x4 parts off my 77, and re-do everything on this 79, because there's some things I think that could have been done better.

 

Opinions?

[bonvo]

what things so you think could have been done better? seems les labor intencive to take the body parts you want off of this one and put them on yours

[yello620]

IF you are selling any of the A/C stuff off of the 79 truck, please let me know.

 

Basically though, i need the underhood parts of it. I already bought all the stuff that goes in the cab.

 

Jason

[Icehouse]

That sucks dude!!! At least you found another truck :D Get it fired up and see if the ac works, it would be cool to have working AC!!! I dream of it :D haha

[ppeters914]

Get it fired up and see if the ac works, it would be cool to have working AC!!! I dream of it :D haha

What? For one or two weeks a year? :lol:

[slodat]

I will be traveling out of the PNW in my dattos, and A/C will be a requirement in my truck.

[RacnJsn95]

Well I sat down and thought about it and I decided the z24i could wait. Hainz kind of made me think to just dump another L20b in it, luckily I just happen to have a runner in the 79 parts truck... SO, took the day to do ratsun stuff. Pulled the L20b out of the 79, and worked on taking most of the accessories off it (intake, exhaust, a/c, smog pump etc)... I'm going to swap on a different head I have, since the head on it is a w58 round port, and my exhaust, and manifold in the truck is a square port. Have a fresh open chamber I'll put on it. I think I might swap timing covers, along with the chain/gears from my other engine since it was new. Other than that, I'll go buy some castrol super clean and duesch it off, maybe scrub it with an old tooth brush or something. Hope to have the other engine out of the 77 tomorrow, so I can swap parts during the week. HOPEFULLY I'll luck out and get another nice weekend next weekend so I can put the engine back in the 77.

 

 

And since my hood wasn't so nice, I decided to clean up the hood off the 79 and get it ready to go on the 77. Decided I'm going to paint the truck mostly flat black, so I went ahead and painted the hood... What do you guys think? I'm going to use the tailgate off the 79 also, and paint it the same way on the outside.

 

[RacnJsn95]

Been working on putting the other engine back together the last couple weekend, but ran into a snag... One of the timing cover bolts was previously broken off in the block from when the PO removed the water pump... Waiting on my Dad to get back from Reno as all of his easy outs are at his work... Hopefully it comes out; if all goes as planned I can start putting the engine in tomorrow.

 

On a side note, has anyone ever done any research on homemade superchargers? IE: The gator supercharger? Somehow I came across it, and they claim they work great for engines 3 liters or smaller, easily producing 6 psi of boost. Strangely enough the book editor's name is Dick Datson (it's a sign!)... So I took the bait, and I bought the book, I'm going to try and make one for the 620, and unilize the smog pump mount for mounting. We'll see what happens, the book is 132 pages, and has 5 variations for building "superchargers"... If it doesn't work, I guess it won't be the first time I've gone for the snake oil gag :P

[RacnJsn95]

Finally got most of the engine together, and put it back in the truck today.

 

 

I took this opportunity to leave the manifolds off so I could see if the LD20II-T turbo manifold and tube will fit in a 620 without hacking the crap out of it. And it did! I did have to remove the stock cast down pipe though, but if the flange where the exhaust bolts to it at the bottom could be rotated I think it would work. Here are some pictures without the down pipe.

 

 

I think it would work good in a 620... I don't know if it would work in a 510 with the stock steering box though? Turbo is a Garret something, .48 a/R on the compressor side. Wonder if this thing would be too small for an L20b? Overall I think a good find.

[lynchfourtwenty]

would be a little better if the turbo didnt sit so far back, puts the down pipe right against the firewall... you should put that sumbitch on there.. make a sealed box to bolt to the top of ur carb hehe.. its kind of a small turbo but it would be fun to see if it worked very well, you would prolly have to richen your mixture a bit..

[Hyspeedz]

Been enjoying this thread a lot, and have learned a lot. What's the status of your situation?

 

Best!

 

 

Finally got most of the engine together, and put it back in the truck today.

 

 

I took this opportunity to leave the manifolds off so I could see if the LD20II-T turbo manifold and tube will fit in a 620 without hacking the crap out of it. And it did! I did have to remove the stock cast down pipe though, but if the flange where the exhaust bolts to it at the bottom could be rotated I think it would work. Here are some pictures without the down pipe.

 

 

I think it would work good in a 620... I don't know if it would work in a 510 with the stock steering box though? Turbo is a Garret something, .48 a/R on the compressor side. Wonder if this thing would be too small for an L20b? Overall I think a good find.