Hi all, I'm a pretty much first time poster here, have been lurking for a bit. Glad the forum is here, it's been helpful. Bought a 93 DD51T with F6a engine, (actually DD51B - the dump body version) which was predictably, not quite what it was sold as. But, it was what I wanted and it's what I have. I've read the 2 carb threads and think I'm beginning to understand how this complicated beast operates, but still have a problem and am thinking somebody here knows the answer off the top of their head. Well, hoping The problem... It starts right up cold, runs well until the temp needle starts to move, then won't rev up and starts to stumble. I can get it to continue to run for a bit with the accelerator pump, but not for long. It won't start again until it's dead cold. There's fuel to the carb and plenty of spark while cranking. And I'm still bleeding the cooling system and wondering if the absence of coolant to the carb could be causing this. It's jacked up in the front (thanks for that tip!) and I'm running, topping off with coolant, letting it sit, repeating, etc. Anyone know what's wrong? Thanks!
I have a friend with a 92 Suzuki I believe and this sounds like what he was telling me as, but he doesn't has internet, so I'm looking for answer as well, have you found one yet? In the meanwhile I'll keep checking around and if I find anything I'll let you know!
I think so... Basically the cooling system cools the carb (yeah, I know, wierd), which is at the high point of the cooling system. Any air in the system finds its way there, the carb quickly overheats because it isn't being cooled, instant vaporlock. So get that little pocket of air out, and you should be golden. Now, as noted, I'm speculating a bit as to the cause/how it works. The folks who know may tell you that it has to do with temps at the choke pulloff. I'm just learning this rig. Finally got all the air out of mine(jacking the front of the truck up helps, as does bleeding the cooling system at the carb, if you can get to it) and it started running better, and more importantly, longer. Then a coolant hose started leaking, same behavior. So I'm reasonably sure that's the problem. Gotta get past that problem to find all the others
hey! thanks for the quick reply! I will surely get to him on that and see if he wants go that way as he wanted to haul to a place I know of that USED to work on them but they no longer have a staff to do repairs, bummer eh? I'm still working on my 96 Carry with a clutch cable problem but with recent back surgery it makes for a hard chore to be sure! But thanks again!
The water to the carb heats the choke mechanism, and isn’t cooling it. If it is air locked or those little hoses get clogged up, and the water doesn’t get to the choke, it never disengages, and you get the issues described. It will run fine until it heats up, and then wants to stall. Once it dies, it won’t run again until the engine cools down, and needs the choke.
