Coolant line out of exhaust manifold-98 burb

**phoebeisis** · 05-12-2009, 09:28 AM

Hey, what is the story of the coolant line that appears to be coming out of the driver's side exhaust manifold on my 1998 Suburban?? I'm curious because there is a faint chance that my coolant leak is related to it(I think the intake manifold is more likely).

I'm guessing that it is some sort of quick warm up gadget to decrease emissions.
Where does the coolant come from- it looks like it must come from the head? The reason it seems so odd is that the exhaust manifold then has to seal against pressurized coolant and very hot gases.This seems like too much to ask of a gasket, but...?

So does coolant actually pour into a hollow in the exhaust manifold? How is it shut off once it warms up? Where is the shut off "valve" ?

Thanks,
Charlie

**GaryL** · 05-12-2009, 09:48 AM

That's not a coolant line, it is the EGR hose.

**phoebeisis** · 05-12-2009, 10:15 AM

Hey, that makes sense-thanks!! I thought it was a coolant line because to seemed to make its way to the water pump.I gotta admit, I couldn't quite see where it went back into the water pump.

It must be a steel line right? So why armor a metal line with that woven plastic fabric that covers it?

Thanks for the info- I couldn't figure out how/why a coolant line would be set up like that.

Thanks,
Charlie

**Crawdaddy** · 05-12-2009, 10:30 AM

well, it's carrying unburnt exhaust gases back up into the intake manifold to be re-burnt. It get's really hot, so that's heat shield fabric to keep from toasting the wires around it.

**phoebeisis** · 05-12-2009, 10:41 AM

Crawdaddy, hey that makes sense- use that fabric to catch and diffuse the heat.It-the fabric- must be some sort of super r fabric-it isn't really very brittle considering 12 years and 210,000 miles.

Thanks guys. Now I'm pretty certain my coolant leak that pools on above the bellhousing and maybe on the back of the block- is from the intake manifold gasket.

Who makes the "best" gaskets to replace them.They were replaced at 161,000 miles by the PO-lasted about 4 years and 50,000 miles-that sounds about right considereing what a problem they are.Yes, he and I use Dexcool- It was what GM calls for,so I use it.Might have to rethink that.

Thanks,
Charlie

**GaryL** · 05-12-2009, 10:48 AM

Use the Fel-Pro gaskets. They are better than GM's.

**phoebeisis** · 05-12-2009, 11:05 AM

GaryL,
Do I replace both upper and lower gaskets?
I noticed that the manifold seems to be two parts? The bottom seems to be metal- it mates with the heads,I guess? The upper manifols seems to be some black super plastic that mates with the lower manifold and the upper FI "stuff"..

I'm guessing I replace all the gaskets, but since I have a coolant leak on the drivers side that causes coolant to pool on the bell housing, it must be the lower gasket that leaks.

Thanks,
Charlie

**Dr_Zero** · 05-12-2009, 01:43 PM

Originally Posted by phoebeisis

GaryL,
Do I replace both upper and lower gaskets?
I noticed that the manifold seems to be two parts? The bottom seems to be metal- it mates with the heads,I guess? The upper manifols seems to be some black super plastic that mates with the lower manifold and the upper FI "stuff"..

I'm guessing I replace all the gaskets, but since I have a coolant leak on the drivers side that causes coolant to pool on the bell housing, it must be the lower gasket that leaks.

Thanks,
Charlie

I had mine changed a few month back you can read it here and I put the part numbers in there just in case someone else might have an issue.

http://www.gmtruckclub.com/forum/new...reply&p=133016

The Fel-pro set I got had everything you could need including another valve cover gasket and distributor gasket and a tube of sealant the cost is around 50-60 bucks but worth it to have good gaskets and everything you might need.
You dont have to take off the upper part you can slip the whole intake to the right side of the motor with the valve cover off, you can replace the upper gasket while you are into it or wait.

**phoebeisis** · 05-12-2009, 04:12 PM

Dr Zero,

I just saw you in another manifold leak thread and responded.

Yep, the MS98000T looks like the right way to go. I don't like to do repairs more than once(of course,Ive done repairs, because of my screwups-many many times-another story, long, slow learning curve)

Thanks,
Charlie
Some Amazon sell has them for $55 delivered.