My 720 Resto

[720inOlyWa]

My learning curve visa vie the weber carbs, has been a steep one. I read and re-read every set up article and trouble shooting guide that I could find, but nothing beats just fucking around with it- good old trial and error. and man, I have had plenty of trials and errors before coming to a greater understanding with mine. Having said this, I am still not sold on the Weber carbs overall. Not that they can’t be made to work well, I just think a good fuel injection system would probably be an overall improvement. (Good does NOT include TBI, in my opinion.)

 

One thing that I noticed may be worth some discussion. My main butterfly shafts were sticking after about a month of driving. I would soak the shafts in carb cleaner, let it soak for a few minutes, then all would be fine again- for another month or so. When the shafts get sticky, the idle does not return to 850 RPM without a little batting of the throttle. Irritating.

 

I went through the set up protocol again and again and, though it ran just fine, the sticky shaft problem persisted throughout the fall and winter. I tried installing shaft bearings on one old Weber 40 carb that I was playing with, but they didn’t really fit right, and that carb is now in pieces in a box (want it?).

 

I noticed that my plugs were in the decent range, if only very slightly blackened. (This engine as not had the rings and bearings done, and had been overheated before I bought it, so I expected this) But I noticed the tail pipe color was blacker and sootier that I would normally like to see. So, after the third carb cleaner soak of the winter, I went ahead and cranked down the main mixture jet by 1/8th turn  just to see what would happen. Well, the tail pipe looks right now and the plugs look fine too. And no more carb cleaning either (at least not yet). I supposed that the slightly over rich mixture was allowing for some splash back onto the shafts, which were lacquering up over time. That, or the float bowl level is set too high, and gas is dribbling down the throttle body are rest, lacquering up the shafts.

 

So my current thinking about Webers is that perhaps they want to be run just slightly on the lean side. (at least leaner than this shade tree mechanic thought) Thoughts?

[Charlie69]

Nice work on the Fudgecycle.

[720inOlyWa]

Another Misdiagnosis: Yahoo, the learning never stops!

Ever since I got things running right, I have noticed an intermittent ‘slow crank‘ situation. It’s as if there is a little bit of hydraulic lock in a cylinder or two that clears right up when I release the key and then stab the starter again. Then, zingo, off it goes. It remedied itself so easily, that I barely gave it a thought. I had assumed (incorrectly) that I was getting some fuel into the cylinders sometimes when it sat. After all, it didn’t happen all the time, or even all that often. I had reasoned, as a novice might, that maybe the float bowl level was a little too high. Problem is, this hypothesis turns a blind eye towards at least two float adjustments I had made while learning about my Weber carb. Oh well.

 

I didn’t give it a high level of concern until the other day, when I had a full load of manure in the back down at the Western Supply store. When I jumped back in the truck after supervising the load up, I hit the key and it just went ‘click’. The headlights were strong, and it clicked the solenoid, so that pretty much narrows down the problem right away: tits up starter motor. This is the first time in my entire life that I have lost a starter, so I guess that aint half bad. Maybe I was long overdue.

 

No problem, I just rolled down that shit slick apron there in the load up area and popped the clutch, and then drove on home with my load. I had to park strategically however, so that I could unload the ‘chicken and chips’ in a spot where I would also be comfortable swapping out the starter motor. Here is where my Nissan addiction actually paid off a little bit, for once. The organ donor truck, still on blocks in my driveway, had a starter that, from the outside, looked to be pretty new. 45 minutes later, the swap out was complete and The Fudgecicle was ready to start on its own again, and, holy cow- that cranks way better now!

 

Who knew how tired my old starter was? Surely, I didn’t. Not until it croaked. And that is the point, really. I am just a shade tree mechanic, a total amateur, rehabbing a sweet old 720 truck just for the hell of it. There is a steep learning curve attached to this experience. Good thing I like that part too. If I stumble in my re-habbing adventure, I hope that others here will learn something from my mistakes.

 

The Organ Donor:

 

[Charlie69]

Now get the old starter rebuilt by a quality shop and put it away for a rainy day.

[720inOlyWa]

I was going to look into this, Charlie. It is just an electric motor, with a Bendix system stuck on the end. That means it is probably the  brushes or something. That is certainly all rebuildable, seems to me. Now to find that quality rebuild shop...

 

 

Ed. / Follow up: Off it went to get tested and rebuilt! there is a little starter rebuild shop out near the Point Defiance ferry to Vashon Island. They said “Come back in two weeks. Sixty bucks.“

[720inOlyWa]

I pulled the engine / transmission out of my organ donor truck today and so you can bet I am going to have some sore shoulders tomorrow. Which is fine since all that I will need shoulders for is to squirt degreaser, kerosene, then water on the donor engine on my engine stand.

 

I hired a guy to help, and he came with an engine hoist. So that was a bonus. It took about two hours, plus cleanup. But I had a lot of parts off of it already. I would have taken a picture, but it was getting hard to lift my heavy old camera... 

 

Morning has come and my arms aint so bad after all. So, for Drakers sakes-  let’s preserve this  ‘before ‘ moment for posterity.

 

 

This engine and tranny felt  pretty darned good, driving it home. It accelerated smoothly and shifted through the gears without any noise or hesitation. The engine will get zero timed and will go into the Fudgecicle while the tranny will get checked out before going into my 85 4x4.

[Draker]

Shame.. no pics

[720inOlyWa]

Anybody know the best way to get old clutch gunk and gear lube off of the inside of the tranny bell housing? Kerosene and elbow grease?...

[720inOlyWa]

Looks like I answered my own question. Three hours and a bunch of elbow grease later, and the tranny is ready to haul of to the transmission shop for evaluation.

 

 

Once you get going, it is hard to stop with the Harbor freights soft steel brush. Mary asked me a good and fair question. “Isn’t it just going to get gunked up again?“ Of course it is. That is hardly the point. The point is, from now on, it is my gunk on there.

[720inOlyWa]

Any ideas on where to get a new clutch boot for the tranny? This one is pretty tired.

 

I should have looked past the ‘made in Thailand’ options on ebay before I posted this. I found a OEM boot for ten bucks.

[84720FourWheel]

I just ordered them from my local Nissan dealer.

[720inOlyWa]

Nothing is ten bucks from our local dealership. Hah!

[720inOlyWa]

Who doesn’t like doing truck stuff- with your truck?!?

[84720FourWheel]

I got it in overnights so the 15 bucks was alright by me.

[720inOlyWa]

I found a shady spot this morning to begin tearing down my grimy donor motor. manifolds off, water pump, distributor, here we go!

 

I will take the short block, with the pistons in, and the head, separately, to get their machinist to check things over as the bearings come apart.

 

[Charlie69]

Looks great!  Want to do one of mine?  LOL

[720inOlyWa]

The transmission from the organ donor truck came back from Lloyds auto this morning. They are our local transmission shop. They took the front cover off, inspected the front bearing, split the case and checked the gears and bearings and bushings, put it back together and ran it through their spin up machine, checking all five fears and reverse. The jobber tag on the transmission said ‘exceptional’. Good enough for me!

 

I drove this transmission for 2 miles before parking the organ donor truck, and I thought it felt fine. So I didn’t really expect a bad report. But considering the pain of pulling a transmission, $62.00 was an inexpensive price for a little peace of mind.

 

This tranny will go into the 4x4 eventually. So I put it in her bed for now. I realize that I will have to plug the speedo cable connection to use it, and that the gear ratios are somewhat different (though I am not sure exactly how different they are just yet). Still and all, this is a great news day!

 

[wayno]

I hate to tell you this, but as far as I know, all later 4X4s had short shaft 5 speeds while that is a long shaft, you will either need to find a short driveline and relocate your shift lever, or you will need to find a short shaft 5 speed.

The transmission from the organ donor truck came back from Lloyds auto this morning. They are our local transmission shop. They took the front cover off, inspected the front bearing, split the case and checked the gears and bearings and bushings, put it back together and ran it through their spin up machine, checking all five fears and reverse. The jobber tag on the transmission said ‘exceptional’. Good enough for me!

 

I drove this transmission for 2 miles before parking the organ donor truck, and I thought it felt fine. So I didn’t really expect a bad report. But considering the pain of pulling a transmission, $62.00 was an inexpensive price for a little peace of mind.

 

This tranny will go into the 4x4 eventually. So I put it in her bed for now. I realize that I will have to plug the speedo cable connection to use it, and that the gear ratios are somewhat different (though I am not sure exactly how different they are just yet). Still and all, this is a great news day!

 

[720inOlyWa]

I hate to tell you this, but as far as I know, all later 4X4s had short shaft 5 speeds while that is a long shaft, you will either need to find a short driveline and relocate your shift lever, or you will need to find a short shaft 5 speed.

 

 

Damned if you aint right, Wayno! Dammit anyway. Hah- the last laugh is on me. 

 

Geeze, I looked under there before and I thought it was the same one. I also checked the ID tag and thought I had cleared it for a match. But I guess not.  Oh well, I will swap this one into my 2x when the engine is done and call it a lesson learned. There’s nothing wrong with the one that’s in there, except is aint nearly as clean.

 

Now to figure out what to do about finding a 4x4 tranny and/or repairing the one I have....

[Lockleaf]

You can have your intermediate shaft shortened to work with that trans if you want. Then you just need a long tail shifter hole cover from a 2wd, and if you have a center console, a long version of that as well.

[720inOlyWa]

You can have your intermediate shaft shortened to work with that trans if you want. Then you just need a long tail shifter hole cover from a 2wd, and if you have a center console, a long version of that as well.

 

 

Certainly worth considering as well. Thanks, Lockleaf. Fortunately, I have some time to mull this and other options as the first push will be to finish up this 2x KC. I need it to be fresh enough to help move several projects forward and right now, with a slightly geriatric bottom end, I hesitate to leave town with it (but I do anyway). So I will mop up this one first and, as I go along, I will get the big push for the 4x4 rehab project organized and ready to go.

 

My problem is, I have driven another 84 720 with a fresh rebuild and a new clutch. It had all the zip and snap that I remember from my 620- and then some. I loved it! So now, I realize what I am missing and can’t live without it.

 

 I have become very fond of this truck, despite its (current) limitations. Even with them, I have logged 14,000 miles on an engine that received little more more than a timing chain and a new head after ‘overheating pretty bad, man.’ upon losing a head gasket. That it has delivered two years worth of service is pretty impressive in itself. It has hauled many loads of topsoil and ‘chicken and chips’ to our gardens in the interim. Once it gets some air shocks and the new motor, it should be terrific for those 700 lb  (and under) loads. It is way fun to drive. And, in complete opposition to my expectations when I bought it at near scrap prices, it has begun to come into its own in terms of cache. I get compliments all the time. When people (often as not, girls!) offer to buy it, I tell them to hold on to hope- I simply can’t live forever.

 

Having said this, I often sit in the 4x4 version, a near twin, and daydream about driving it. By comparison, it feels like a totally different animal, even sitting in my driveway. You step up into it, instead of sliding right in. It feels a lot stiffer, way more brutal than the gentlemanly 2x KC. I am really looking forward to tearing into it’s innards before the snows fly.

 

By then, it will be time my first oil change with the 2x heart transplant and it should be cleared for unrestricted use. I have been mulling the replacement of my precious radio delete cubby with a radio.  Mulling. (I can mull a long, long time.)

 

Fun stuff. Like PosTits... only in a different way.

 

[720inOlyWa]

This morning, I removed the black carpets and the turn signal switch (along with the black plastic steering column housing) and the black jump seats and back support padsmfrom the organ donor truck. The carpets are pretty dirty, but may be rehab-able. In any case, they are much better than the ugly replacement rugs in the 4x4 right now. I did a preliminary shop vac treatment and put them away for now. They will go into the 4x4 eventually,along with the jump seats (I go for the black over the tan, obviously).

 

With these last little bits removed, this afternoon I will go down and sign off on the sales offer at the PickNPull and then watch it roll off into the sunset.  All together, I gleaned a whole bunch of important components and parts for a net cost of about $120. Not bad at all.

 

I also stopped by Johnstons machine shop this morning, out on S. 92nd, to go over the delivery of my engine components. Can’t wait for that adventure!

[720inOlyWa]

So long, organ donor truck Thanks for your guts!

 

(Damn- forgot to take out the rear glass and save it!)

 

[Charlie69]

Looks like you forgot a whole bunch of other parts too!  LOL

[720inOlyWa]

Kind of a milestone morning as I pulled the timing chain cover and head this morning. Removing the head is a big reveal as it afford me the opportunity to take a 1 inch flat chisel and carefully clean the block deck to check for cracks around the head bolts. More than one Z 24 mech has told me this can happen with this engine and that if it does, it is a deal breaker for that block.  I suspect this happens in blocks that have lost a head gasket and overheated badly, and so far there is no sign of that history here in the donor motor. The head bolt holes all look clean and crack free. Good news for me.

 

This also goes for the head itself. The melty bit is intact, indicating it never overheated badly. The thin area between the exhaust and intake valves shows no cracking at all in any of the cylinders. (I have yet to wire brush and inspect with a magnifying lens, however.) The guides look reasonably worn, and again, no cracks upon gross visual ispection. Perhaps more good news for me.

 

One thing puzzles me, however. All of the cylinder walls look great. I mean, really good. A light clean up bore ought to do the trick, if my guess is correct. But cylinder number 4 had quite a bit of flakey carbon just sitting on the top of the piston. Maybe three teaspoons of loose carbon, with a few flakes over 3/4 inch across. This baffles me. Sure, there were some carbon flakes in every cylinder and the expected buildup on the valves and head, but number 4 had a lot of carbon. I would have thought that it would have broken up and exited the number 4 exhaust valve, but it didn’t.

 

Is this a result of years of just cruising aroud the local area and never letting it warm up all the way, or breathe hard down a freeway? Shitty gas? It isn’t concerning so much as it is puzzling. Number four plugs, like the rest, seems like it was actually running a little lean- at least during the end times for the organ donor truck. Do you suppose it was run cold and rich at some point, and for a long time, to build up so much carbon in number 4? I wonder.

 

IMAGES?

I would gladly share photos of my progress, but Photobucket says my plug ins are blocked. Then they offer a barrage of ‘you might also likes’ instead of the image download link. I think we may be approaching the end of my association with photobucket...

 

...and just like that- it works again!