View Full Version : motor help

09-22-2009, 05:09 PM
I have been driving my international scout with the 633t (SD33t?) in it around for the last two to three weeks with no real problem. It seemed to be running fine so i was concentrating more on the electrical problems than any thing else. Today I was driving over the 1-90 pass here in washington and the diesel just dies on me. I thought I'd run out of gas so I called the tow truck and they took me to a gas station where I tried to put more diesel in it. The breather tube has always had problems and it takes a while to fill up but this time no gas was going down. I fit about a gallon in and then the tow truck guy started her up and off she went, except now there was absolutely no acceleration. I have the tow truck guy take me to the closest diesel mechanic shop who after an hour of futzing around decided that it was the fuel filters, which i do agree needed to be changed and was planning on it but had not experienced an previous problems to warrant immediate attention. The scout ran fine for about 20 miles when it lost all acceleration and I could go like 3 miles an hour if i was lucky. I would turn it off, let it sit for a while, prime the motor with the little hand pump and start it up again, it would run a little while and then lose all acceleration again, I eventually just ended up parking it in a parking lot and getting a ride ellensburg so I can be to school on time tomorrow.

Just to recap - was driving fine, lost acceleration and then died, got it towed, had a diesel mechanic look at it, they replaced the filters, it ran fine for about 20 miles, continued to lose acceleration and then die, wait for me to prime and restart, run for a couple of miles, die etc. The mechanics did bleed the injectors I was told.

Any help will be highly appreciated, I love this truck and really want her to be in good shape again. :(

09-23-2009, 01:01 AM
I had a similar problem with mine... turned out that the #4 piston/cylinder was bad. The pistons are made of a softer metal than the block, so they expand and contract much faster than the rest of the engine when they get hot and cool down. If they get over-expanded, like mine did, they'll run OK for a little bit and then seize up the engine once everything gets hot, say after 20-30 minutes of driving. Let it cool down again and it'd start back up fine. If it doesn't end up being something small, you might end up having to take the head off and inspect the pistons and cylinders.

09-23-2009, 10:03 AM
So one of my pistons/cylinders might be bad? It doesn't seize up as much as gasps to a slow stop after driving like an utter dog. Could it be possible that the throttle cable is not functioning as it should, or perhaps the fuel pump is stuttering to its death? What are the symptoms i should be looking for with the piston issue, overheating after 20/30 minutes of driving? Thank you for the information though, it gives me a place to look if following the fuel fails.

09-23-2009, 10:31 AM
Mine would die pretty suddenly with that bad piston. Not much of a warning, but my engine was quite a mess when I got it. There was more than just the piston that was wrong with it.

Check your injectors. They're actually quite cheap to rebuild (15 bucks a piece, I believe), and it's not going to hurt your engine one bit to get it done.

Also, try bypassing your hand pump and installing an electric fuel pump. I mounted mine on the firewall, but you can put yours pretty much anywhere. Another common way is to put it on the frame. You said that it would work once you charged the fuel system back up again, so your hand pump might be leaking air pretty badly. Mine was, and it was just easier to get rid of it. The electric pump works quite well with the system anyway. The original "fuel pump" was the injector pump sucking fuel from the tank. The electric one will assist it by actually supplying a constant flow of fuel and not making the injector pump work nearly so hard for fuel. And your return line takes all the extra fuel you're not using back to the tank, so there's no problems with it.

09-23-2009, 06:40 PM
Well I'm gonna get her towed to my apartment parking lot, it starts up and runs decently again but from what you mention it makes me reluctant to drive it the last half hour to home. Once it gets there I'm gonna go through the fuel system, I've been looking at the electric filters and from what you've said it seems like a good investment. The injectors probably will be next on my list for sure now since they probably need it and it doesn't sound like it'll break the bank. Urg, I was hoping to concentrate on the curtailing of the rust for the time being but it sounds like I'm gonna be spending more time under the hood now. Thanks again :)

09-24-2009, 12:53 AM
Just start with the small stuff before you think about doing anything big. It's very unlikely that you've got anything major wrong with the engine.

09-24-2009, 09:18 AM
if the engine idles as it did before the overpass issue, dont waste your money on injectors, if there is no smoke or missing it wont be an injector, to prove this to yourself, while the engine is running crack open each injector line, this will cause the injector to lose pressure & drop the cylinder, its just like pulling the plug wire off of a gasoline engine, if ,when you crack the line open the engine starts to miss or change its firing characteristics the injector is good.
I would look for fuel leaks from the transfer pump back to the tank, a pinhole in a diesel fuel line will cause the transfer pump to not pull enough fuel to the pump & cause the problem you are having, adding an electric pump is just covering up the real problem, the truck ran for a hundred years without one right? to test the problem of bad fuel line put a know good hose on the pump & draw fuel out of a diesel jug or pail or dog dish or whatever. if the problem persists, pull the pump & have it tested befor rebuilding it, the pumps or fuel distributors like to be rebuilt at about the 60k mark they are know for wear in the throttle shaft causing the pump to suck air. giving the engine slugish performance, but they will idle, because that circuit is not being used at idle, its usually worn at the highway position because this is where they stay most of the time.

09-24-2009, 06:44 PM
Ah thanks for the fuel line info, I'll try that. Although the scout just only turned over the 3k mile mark so do you think the distributor could go bad that early? Also, could the primer pump some how get a bad seal and allow air into the system? I only just got the scout back to my apartment and plan on checking things this weekend.

09-25-2009, 12:45 AM
Depends on a few things. The injector pump could be getting worn. And yes, you could have air leaks in your hand pump. Mine did; that's why I eliminated it from the equation by bypassing it. No hand pump = no air leaks for me.

Btw, how certain are you of your mileage? Is that all original or have you had it rebuilt?

09-27-2009, 02:15 PM
even if the truck had just 3000 miles on it is still 150 years old, fuel hose are rubber just like tires they dry rot & fuel sitting in them eats the rubber, have had fuel lines that have collapsed on the inside never giving any indication from the outside that they were bad, causing not enough fuel enter the injection pump, also seals are a problem in the pump, even with on 3 k on them. you have a definate fuel delivery problem.

09-28-2009, 01:37 PM
Should I just go about replacing the lines while I'm at it? Any reason that it would have come on so suddenly after driving decently for a while?
I'm the 3rd owner, the original owner kept it garaged for most of the time and my ex boyfriend had other cars to drive long distances so the binder pretty much was his around the town toy so I'm pretty certain on the mileage the odometer reads.

09-28-2009, 02:46 PM
It's not going to hurt anything to replace the lines. I replaced the plastic lines on mine with rubber and ran them along the frame instead of the original placing of along the body. The set up works just fine for me.

Have you ever run bio diesel through your Scout? That can be pretty nasty stuff to rubber and plastic lines; it just eats away at them from the inside out so you'd never know there was anything wrong with them other just from looking at them.

09-29-2009, 05:09 PM
You can get rubber fuel line that is made for diesel..Also if you do replace your lift pump... DO NOT use an off the self gas pump. Get a pump that is made for diesel. example airdog or fass fuel system

10-13-2009, 11:21 AM
Okay, so I got her running good again, emptied and cleaned the tank and refilled it with new diesel, replaced the fuel line and gave her an oil change and she accelerates well now. The only problem is on the way I discovered yet another electric gremlin. It has to do with that little black box right next to where the hood latches, sometimes it doesnt give me a problem but right now, unless i jumper it, it kills all electrical when I try and turn the motor over. If I go out and jiggle it it'll give me basic power, lights come on ect, but when I try and turn her over I loose all electrical again. Any ideas would be greatly appreciated and if anyone knows what the box is so I can possibly buy a replacement would be awesome.

10-13-2009, 01:57 PM
Where all the wires come through the firewall on the passenger side, right? That's just the connections to mate the dash wiring harness to the front wiring harness. If that's not what you're talking about though, you might have to take a picture. It's been so long since I had the original wiring in my diesel that I've forgotten what most of it was. I tore everything all out when I put in a new harness.

10-13-2009, 02:26 PM
That makes sense, I just wasnt sure if it was the Gold Box that I kept on getting when I was googling to see if I could find any info, something is telling me that the diesels don't have a gold box. Its on the passengers side of the hood latch, two open connections on the top and then a rubber boot with, i think 4 contact tabs on the inside, lots of green and black wires. I'm assuming I might be getting a faulty connection which could be causing my problems but I dont know why jumpering it from the battery would cause it to work. I would jumper it now but I forgot which terminal to hook it too and I would rather not fry my electronics.

Could a semi dead battery and bad terminals be causing this problem? Giving enough power to light up the dash but not enough to start her up? The only thing that confuses me is that I loose all power unless i turn the key off and back on. Damn gremlins.

10-14-2009, 04:32 PM
Would it be worth me putting in a remote solenoid to solve the problem of the BHC?

richard kuyper
10-16-2009, 09:16 AM
if the battery is bad replace it a diesel takes a lot off power to start and yes look at al the conektors

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