JeffMoss1
Jeff
Hi guys,
I haven't been around for quite a while now. Not sure if any of you guys will remember me. I basically learned how to work on engines from this forum though, primarily was posting like 3-5 years ago. Anyway, what's good is that my van, after having rebuilt the thing, has been running really well for quite a few years now. The large majority of the components have been replaced and the engine that I rebuilt and put in I got from Rob (69oiler i think?). So first and most importantly I'd like to say that I'm psyched to see that you guys are still around and still working on these awesome trucks.
Now for the problem that I can't seem to solve by myself.
For the last year or so I've been noticing air bubbling up through my overflow reservoir. For a while I was driving the van quite regularly and every time I'd park it and turn the engine off, I'd hear the bubbling. My concern was that a head gasket leak was the problem, but I decided that since the coolant level was pretty much remaining constant and I wasn't seeing any over heating issues, that I'd just let it go and see how it plays out. Drove it for about a year like that, often regularly. A few months ago it started to get worse and was slowly belching coolant out of the overflow also. As my coolant level went down, I'd eventually have to pull over when I saw temp cruise over thermostat temperature and fill the system up with coolant/water that I just started to carry with me. When running the engine you can watch air bubbling up from the coolant reservoir constantly. Steady stream of bubbles.
So haven't been driving it much lately since the problem has been pretty annoying to deal with. Finally getting around to working on it now, so here's what I've done:
Compression test results:
Engine warm, 520PSI after ~8 cranks on cylinders 1,3,4,5,6,7,8. 490PSI on cylinder 2.
Warmed up the engine and put 120psi air through my modified glow plug compression fitting. Watched the overflow reservoir for bubbles. Nothing on any of the cylinders. In hind sight I think it might have been more conclusive if I'd removed the radiator cap and watched for bubbles directly in the radiator, which I actually did for about 2/3's of the cylinders after thinking about it later. So long story short, this test either turned up negative or inconclusive, whichever you'd prefer. ( could do it again if you guys think it's worth it.) Another thing about this test is it takes me quite a while to do it. I'm concerned that the thermostat will have closed pretty early on in this test process, do you think that matters?
Finally, I bought a combustion gas tester and just ran that test a minute ago. Warmed the engine up until the thermostat opened and put the tester on the radiator. Air's coming out of the radiator so fast that I didn't even have to pump the primer ball, it just bubbled through the tester by itself. Did the test twice, fluid remained solid blue the whole time, left it on there for about 3 minutes each time. To check the test I tried drawing some air into the tester directly from the tailpipe and that stuff turned bright yellow in only a few pumps.
No oil in the coolant.
Any thoughts? I'd really love to have something conclusive before I do surgery (if you know what I mean.)
Jeff
I haven't been around for quite a while now. Not sure if any of you guys will remember me. I basically learned how to work on engines from this forum though, primarily was posting like 3-5 years ago. Anyway, what's good is that my van, after having rebuilt the thing, has been running really well for quite a few years now. The large majority of the components have been replaced and the engine that I rebuilt and put in I got from Rob (69oiler i think?). So first and most importantly I'd like to say that I'm psyched to see that you guys are still around and still working on these awesome trucks.
Now for the problem that I can't seem to solve by myself.
For the last year or so I've been noticing air bubbling up through my overflow reservoir. For a while I was driving the van quite regularly and every time I'd park it and turn the engine off, I'd hear the bubbling. My concern was that a head gasket leak was the problem, but I decided that since the coolant level was pretty much remaining constant and I wasn't seeing any over heating issues, that I'd just let it go and see how it plays out. Drove it for about a year like that, often regularly. A few months ago it started to get worse and was slowly belching coolant out of the overflow also. As my coolant level went down, I'd eventually have to pull over when I saw temp cruise over thermostat temperature and fill the system up with coolant/water that I just started to carry with me. When running the engine you can watch air bubbling up from the coolant reservoir constantly. Steady stream of bubbles.
So haven't been driving it much lately since the problem has been pretty annoying to deal with. Finally getting around to working on it now, so here's what I've done:
Compression test results:
Engine warm, 520PSI after ~8 cranks on cylinders 1,3,4,5,6,7,8. 490PSI on cylinder 2.
Warmed up the engine and put 120psi air through my modified glow plug compression fitting. Watched the overflow reservoir for bubbles. Nothing on any of the cylinders. In hind sight I think it might have been more conclusive if I'd removed the radiator cap and watched for bubbles directly in the radiator, which I actually did for about 2/3's of the cylinders after thinking about it later. So long story short, this test either turned up negative or inconclusive, whichever you'd prefer. ( could do it again if you guys think it's worth it.) Another thing about this test is it takes me quite a while to do it. I'm concerned that the thermostat will have closed pretty early on in this test process, do you think that matters?
Finally, I bought a combustion gas tester and just ran that test a minute ago. Warmed the engine up until the thermostat opened and put the tester on the radiator. Air's coming out of the radiator so fast that I didn't even have to pump the primer ball, it just bubbled through the tester by itself. Did the test twice, fluid remained solid blue the whole time, left it on there for about 3 minutes each time. To check the test I tried drawing some air into the tester directly from the tailpipe and that stuff turned bright yellow in only a few pumps.
No oil in the coolant.
Any thoughts? I'd really love to have something conclusive before I do surgery (if you know what I mean.)
Jeff
