Bubbles in coolant recovery tank

[NH2112]

Yep, on the 6.5l I just swapped in. :confused: However, I'm not 100% sure it's a head gasket, because it stops after a few minutes and the upper rad hose never gets hard like I think it should. Maybe I'll pull the coolant crossover sometime soon and see if I get bubbles out of either head....if so, I'm definitely finding a shop to do the work in tongue.gif

[More Power]

Shouldn't happen even on a brand new engine/rebuild, but the heat-curing compound used on Fel-Pro head gaskets can take a few thermal cycles to fully set.

I'd run it through a half dozen warm-up/cool-down cycles before passing final judgement.

Jim

[john8662]

Maybe it's just burping and getting air out of the system.

When you filled the engine, did you open the air drain valve located on the thermostat crossover pipe? This is very important in getting rid of the air.

J

[Ratau]

I get the same "Bubbles in coolant recovery tank"

Won't it create a small passage in the gasket and keep on leaking pressure into the cooling system?

Will it help to re torque the head bolts, I still got the old style bolts?

[NH2112]

No, I never did bleed air at the gooseneck, and as I was shutting the hood in disgust last night I thought about it but decided I'd do it today. And the fact that it only bubbles for a few minutes makes me think that it's not a head gasket because that will obviously pressurize the water jacket any time the engine's running.

One thing's for sure - the truck gets up and moves! I haven't really gotten on it because at this time I only have a pipe about 18" long coming off the turbo so it can get a little loud, but today I'm going to finish up the exhaust and take it out on the road with a load in the bed to get a feel for all that power smile.gif

[NH2112]

Well today I finished up my exhaust, checked at the bleeder for bubbles in the coolant (none), and still see bubbles in the overflow tank. But I still don't think it's a head gasket issue (or crack in the water jacket) because of the reasons I mentioned above.

Anyway, I took the truck out on a test run after finishing the exhaust, out a road that has a decent-sized hill on it. I was hoping to get behind a semi so I could floor it to get around him when he moved into the truck lane, but that didn't happen so I just passed the guy in front of me LOL. The truck has a LOT more power, so much more that I find myself going WAY faster than I plan simply because I give it foot-feed like I used to have to do. The engine's basically being choked by the exhaust (right now I just have it running through a single side of the old dual exhaust) and there's still some fine-tuning I'll need to do to the whole engine....change the oil again, check and perhaps adjust timing, see why there's a hesitation when cold, get rid of the AC compressor and vacuum pump, install the idler, clean up the bird's-nest of wiring I left during my "freezing fingers wiring job", etc. Later on I'll get a 3" system made, probably using a FLowmaster because I love the sound of a 6.5l TD going through one. I may end up installing a 2" body lift to gain more room for the exhaust, and also to allow room for slightly bigger tires when I put the 3.73 14-bolt in (and maybe find a C20 front end to bolt in so the wheels match!)

[john8662]

Got Gauges?

Small exhaust and a turbo engine don't like one another.

Pyrometer, and Boost Gauges are going to need to be on your Christmas list, or perhaps an early delivery.

I know of a pretty good gauge holder that will work in the 81-87 style truck.

[NH2112]

Gauges are a priority once Xmas is past...actually, I think I have a set somewhere, that came with the ATS turbo I bought a long time ago, but haven't been able to find them. But in any case they're not that expensive, and will tell me a lot about what I need to do to fine tune everything.

I'm thinking of modifying an under-dash 2-hole bracket to mount on my A-pillar, just above the rearview mirror eyeline. Even if I have to weld it on, I want to put them there.

[Subzilla]

http://www.73-87.com/7387garage/interior/gauges_dashmounted.htm

I used the link above as a guide to mount my tach, pyrometer, and trans temp gauges in the dash. I think it looks pretty slick and clean. I can easily keep an eye on them and not have any of my windshield view obstructed.

[john8662]

Subzilla,

Thanks for the article!

Those gaugs installed in the dash look awesome. But, I'm not that brave just yet, and I've got a dash mat covering some of that area.

The holder I'm thinking of using is an above dash pod that holds three gauges, I'm going to mount it between the visors right next to the windshield, but above the rear view. The pod will be mounted directly to the headliner.

Viewing the gauges from the location won't be as easy as on the dash, but they'll be out of the way and be there when I want to take a look. I'm going to use them more for a reference, not to drive by.

[NH2112]

BTW

I pulled the blown 6.2l apart today, and found that a dropped valve caused everything. The valve stem broke, causing the locks to unlock and eventually the valve beat a hole through the piston top. That valve's pushrod was in the oil pan when I took it off a few weeks ago. There's a nice chunk of metal missing from between the valves in the head, the rod is bent and twisted, and the cylinder wall has a nice hole in it.