hey you all, got in my truck this afternoon and started it up, I have a weak starter so had to give it some gas (diesel)b4 it got started, I noticed the GEN light come on in my dash and the oil pressure diped to zero, pulled the key out and it stayed running. I jumped out to pull battery cables but after about 30 seconds it shut it self up. I've heard about diesels running backward so I figured thats what happend. Coud it have been the weak starter or some other problem. Thanks in advance..

 

I guess I've never personally heard of one of ours running backwards. My guess though, is that your starter contacts are more than likely fried, and this caused your starter to stick, which in turn didn't allow your fuel shutoff solenoid to cut fuel to the engine when you turn the key off. Do a search on starter contacts and you'll have quite a bit of reading on your hands. You can get new contacts for around $30. Good luck

 

I have heard of it happening from the TDR, very rare though. The guy that had it happen had the engine fan spin off.

 

Thanks guys I going to replace my starter ($140.00 rebuilt) hopefully that will prevent any future problems

 

Give this site a try:
Foster's
You can rebuild your starter cheaper than $140.

~Rob

 

I have seen a 6-71 run backwards after it was stalled out, white smoke came out of the air cleaner the thing barley ran and had to be stalled out again to stop it. I think your starter contacts are a fualt something happened to me starter would keep running when the key was shut off.
Fixed that one real quick!

Jack

 

I can happen, depends on the shape of the cam lobe on the fuel pump and service the engine is doing, heavy loads and lugging till stall are how it happens usually.
John Deere 2 cylinder diesel will run backward if you do it just right (or wrong). I've had it happen, blows oil out the oil bath airclean and scares the daylights out of ya.

Early cam lobes for the pump look like an intake or an exhaust lobe, the pump plunger is getting charged with fuel the whole time right until the injection event and then is getting charged with fuel until the next one.

The later 720/820 diesels had a different shaped lobe on the cam to prevent this. Instead of looking like a normal intake lobe it was held at full stroke until just before the injection event when it was returned to fill the plunger and then it injected fuel, but it was held at full stroke until just before the next event.

 

I did it my Isuzu NPR auto the other day was going forward very slow and shifted to reverse . I was bearly rolling the thing bogged way down and ran backwards for about 30 secs.. Sounded odd and smoked alot..

 

$20 worth of starter contacts from www.fostertruck.com should fix it right up.

I've seen lots of diesels run backwards but never upon starting like Alex feels his did.
Most times it happens rolling backwards in a forward gear.

 

Thanks again guys, I'll get to work and I'll update conditions in a couple...