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Bought an Isuzu Diesel PUP - What do I do first?

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Hey guys - after several months of searching, I'm now the proud owner of a 1981 Isuzu Diesel Pickup. It's a 2WD 5-Speed. It's showing 197,000 on the clock but the original owner claims that 90,000 of that was pulled behind a motorhome.



I'm going to do the obvious and change the oil and filters but what other maintenance should I do? Rear end, transmission fluid? Any recommendations?



I've read that the first thing to do on one is replace the timing belt. Any opinions to back that up? Any ideas as to how hard of a job it is?



In the back of my head, I would almost try and put a turbo on this thing but it might be a waste of time. Maybe a good use for an HY35? :p



Thanks for the help guys - any tips are appreciated!
 
You have one of the finest small pickups ever built. I bought a new one in 83, 4wd diesel. Put over 300k on it before I blew the engine because of a blown radiator hose. (Hader on Cruise in the middle of NV,, engine got red hot before it froze. )



The engine suffered cylinder wall and piston destruction,, but the bearings, cam and all other moving parts were still ok.



I sleeved all 4 cyls back to stock bore, new pistons, and of course replace all insert bearings and am bearings, ground the valves and we were back in business for another 100k.



After 13 years in the IA winter roads the body fell apart. I turned the running gear over to a friend of mine,, I gotta find out what he did with it. I wish I had it back.



The timing belt should prob be replaced, although I did not until I rebuilt the engine. It is not hard to do,, cept you should have the book so you know how to time the camshaft and pump.



You have one heck of a good engine,, BTW I also had two Chevettes with Isuzu diesel engines, both had over 200k with no probs when I sold them. Wish I had them back too!!!



Also,, wehn I first bought that pickup,, there were turbos offered by OEM for them. I think later years they were factory options. . dont rightly know for sure.



You are gonna be one happy dude with that machine,, just treat er right, maint and all ,, I neve turned the engine over 3000RPM, was religious about oil change etc and never had one bit of prob cept as noted above stupid error not paying attention to temp guage.
 
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Is there one certain service manual that I should go by? I really haven't come across what would seem to be the "bible" for these trucks. Any recommendations on which one(s) to get and where?



Thanks for the reply - I'm feeling pretty good about this purchase.
 
I was only half serious, Forrest. I've read that the early models with turbos had problems with connecting rods. The internal components couldn't withstand the added power. I'll probably leave this one alone for a while.



I'm going to pick it up this afternoon. I went and looked at it yesterday and did notice that it was idling kind of rough. The sound was smooth but the little truck actually shook when when it was sitting at idle. Is this normal or do I need to check some things?



Thanks again for the help.
 
My brother has one he bought new back in the early 80s. He's a diesel mech and he said the engine is the same unit they ran in a lot of refrigerator units for trailers. He still uses it around the farm but its a real PITA to drive. I'm 46 and I can out-run it to the mail box 1/4 mile away :D



These trucks had lots of radiator/cooling issues if I remember right.
 
I ordered the Service manual from the publisher as noted in the back of the owners manual. Prob could find one on the internet.



The idle should be 100% smooth. All fireing sounds the same.



It is a small engine,, about 87hp I think but dont lettem foolya. I pulled a loaded Septic truck (F600) that was completely dead weight out of a lawn uphill up over a hump enough to get it started. Did it by taking the engine up to 3000 and slipped the clutch blew black smoke out the side straight pipe impressed the s... out of those watching who made the assumption that little thing had no chance.



I never had one bit of trouble(cept as noted above),, and for that matter never heard of anyone who did.



Ask the man who own(s)ed one!!! (A little packard there)
 
My friend bought an S-10 Chevy equipped with the Isuzu diesel. The shifter would rattle the bones out of your right wrist, it belched black smoke,was slow as hell,but ran and ran without problems. He replaced the H2o pump at 140,000, ran bookoo Mex. fuel through it, and it finally succumbed to lousy maintenance at 200,000+ miles. He hated that truck but it never let him down>
 
I have a factory workshop manual for an '84 P'up. Should be mostly the same as yours. I'd gladly "Pay it Forward" if you want. It's a bit beat up, ripped along the spine of the book. It's in 3 pieces... but easily readable... and free... .



Some advice:

They have a timing belt. Change it... and take the radiator out to do it.



Don't turbocharge it. The connecting rods won't survive it for long. #3 breaks first and puts a hole in the block. They usually keep running though.



Enjoy your truck. They are pretty bulletproof. I sold my '87 at 300k miles. It's still going, but very rusty.



Joe
 
Joe - that would be EXCELLENT! I'll send you a PM with my address and other details.



Yeah, I've decided against putting a turbo on it. I've read the same things that you described. Nothing I can do to this truck will give me any kind of power sensation but I will put some sort of high-flow air filter on it and it needs a new exhaust system done and I may go a little bigger just for kicks.



I'm also going to change the timing belt. I have a sneaking feeling that this truck has never had any major maintenance done to it, but I could be wrong.
 
crank the timing up as far as you can till it barely starts and turn the fuel screw in a lot and get a straight pipe and a k and n filter it will go like hell !!
 
I had a 1980 Chevy LUV gasser which was nothing more than an ISUZU that was imported by Chevy. Also had a 1996 Rodeo. Both were great trucks. The main issue I see you facing is a general lack of parts. ISUZU is famous for ending parts supply after a few years. Also they have pulled out of the US market for passenger vehicles. Good luck!
 
These same little engines were used in forklifts, with just a few changes. The forklift version has a cast front cover, with timing gears instead of belt. The hydraulic pump (for the forklift) is also driven off the front geartrain. Great engines. I bought a 1986 Isuzu with hopes of fixing up/restoring, but a friend wanted it more. I had the factory 2 flue radiator recored with a 3 flue. He found a 1992 Isuzu (less the gasoline engine) and swapped parts from the 1986 into it, using a forklift engine. He now has a unique little truck. They are great engines.
 
Timing belt! I had a '82 Izusu IMARK 2-door 5 speed. It was a real pleasure, fun to drive because you had to drive it hard! Unfortunatly, I failed to change the timing belt in time, it's time was 137K! Unless you know that it has had a recent cam/timing belt, change it. Other than that, flush/fill the cooling system, inspect all hoses and drive it! I had mine for 5 years and never even had to replace a glow plug! Wish I had changed that belt...



Did learn that lesson though, bought an '86 Diesel Jetta new and put 300K on that one. Inspected that belt regularlly and changed twice. Was still running strong when I let it go.
 
When I had the gasser Rodeo, the recommended belt interval was 75,000 miles. I brought it in to the dealer for an oil leak at the front of the engine, turns out it was the front cam shaft seal. I asked the service writer if they had to remove the timing belt to repair my oil leak, she said yes. I said I'll pay for a new belt then, the labor was under warranty 'cause of the cam seal leak. Score! That saved me some coin.
 
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