96 heater hose connection leak

[EdH]

What's a good way to fix a leak where the heater hose connects to the intake manifold? Had it to dealer once (and last time), but it started leaking again. Is there a replacement for the funky leak prone connector?

[Ketch]

I just fixed the infamous intake manifold gasket leak back in December and she started leaking again this June. Thought I had screwed up. Then I notice it leaking around the intake manifold coolant fitting, like yours. I thought I'd try tightening it, but just a touch of the wrench and it broke off like it was made of fudge.

It took me three hours to chip the remaining part out of the threads down in the manifold. Even though it is metal, its non ferrous I guess and the magnet did nothing to retrieve the broken pieces that fell into the manifold.

Tommorrow I'm going to get a new part from dealer and then find a matching tap to clean out the remaining part which seems to be fused to the manifold threads.

Once I get it to where it will accept a new fitting, I will open the coolant drain bolt in the bottom of the block and run the hose through the fitting hole. Hopefully this will flush out the bits of the old fitting that fell into the manifold. Else, they'll end up destroying the water pump or lodging in the radiator.

There may be a reason why this thing deteriorated. I know its not my coolant mix. Its exactly 50/50 Dextron to distilled water into a fully flushed (including draining the block) cooling system.

Such a shame. We have just 60,000 miles on this (a 1999 Suburban LT 5.7L) and this is just one of a string of problems related to cheap materials and poor quality. I may never buy another GM product again after this. GM, I hope you are listening.

[Ketch]

EdH, I noticed in another discussion we had about the Dexcool versus regular coolant, you mentioned you have a shop manual. Would it be possible for you to look up this fitting size and see if it indicates the thread count per inch?

THanks

[EdH]

Ketch; sorry, no luck in manual. Good picture but no specs. I did Google it and found a very related post; http://forum.mpt.org/messages/9/4156.html?1082782460. Interestingly enough, this is the solution that I was contemplating. Now it's a given. Hopefully since the dealer replaced it last year it will come out easy. Just found out yesterday while checking brake linings that it has metric lug nuts. I wonder if that intake thread is metric too? That type of hose fitting (referred to in link posted) should be common enough to be able to find either thread...I hope.

[Ketch]

Originally Posted by EdH

Ketch; sorry, no luck in manual. Good picture but no specs. I did Google it and found a very related post; http://forum.mpt.org/messages/9/4156.html?1082782460

EdH, thanks, this really helps alot. I read that post - wonder if that guy hangs around here somewhere. His post basically confirms alot of what I've already done.

That fitting is made out of "pot" mettle. Same stuff GM engineering was on when they designed the thing....

One dealer I called says he stocks a steel one but was out right now... the other said its just whatever GM sends and did not know about a steel version so now I'm not so sure there actually is a steel version (why would there be two versions anyway.) I'll take my magnet with me to check cause the so called pot version is of course non-magnetic.

Anyway, here's my experience so far: when I got the connector pulled away, I was left with the remainder of the fitting down in the hole. Oh joy, another great challenge in my life......but great minds think alike - like the post you found from "Jimb", you just get a hack saw blade - I used one from my saws-all so it was already narrow enough. I have a handle that accepts the saws-all blades. (I would not recommend using a freakin saws-all on the engine at this point). Feeling like Dr. Kildair, I carefully cut down parallel in three places just level across the very tops of the manifold threads. This enabled me to then carefully pry the pieces out. Except they fell into the hole. But I have some of those little computer keyboard vac accessories that work on the shopvac so I can get into the hole and suck out the pieces which are just sitting down there. I also will shove the hose in there and, with the block plug pulled, will attempt to flush the block straight down through the engine. Have no idea what path it will take but I will also strain whatever comes out to check for debris.

As soon as I get the part I'll be able to go to specialty hardware store and measure the thread count (pitch if metric). Most of the engine is metric but hey its GM engineering.

Next I'll try to clean the threads with a tap or thread routing tool of some kind. Worse case is that the threads get too damaged to hold new part. If so, I'll need to go to oversizing and retrofitting a brass fitting or something. I wonder if there is some electrolysis issue that led them to use the pot metal. If I use something conductive, it may cause a problem??? Or maybe they used that because its so close to the hot wire of the alternator and too many mechanics were shorting out when they detached the hot lead and it rested right on this fitting.....Merlin, are you around here somewhere?

So, as soon as I get the other car back from wifey, I can go find the parts and I'll post the thread count etc.

Thanks for the help.

[EdH]

So are you going to use the oe fitting or a regular hose connector? Just thinking, if there was such a thing as a steel oe connector, why couldn't you just run a good ground wire to it? Seems like that would take care of the electrolysis problem for the whole cooling system. Keep us posted.

[Ketch]

In searching around for this fitting, the third dealer I called yesterday knew his stuff. He said GM had switched over to steel fittings. I took my magnet and sure enough it is steel.

Only problem was they could not tell me what thread count it is. I tried to clean out the threads without a tap but the old pot metal was fused so well it would not budge. So I needed to find the correct size and type of tap.

Trying to figure out what size and type of threads was lots of fun. Yup. Sears and first two hardware stores were not much help but the third knew exactly what I was dealing with. Before I even basically told him what I was trying to do he asked me if I was by chance trying to fix a Suburban with rear heat. Turns out that particular store has dealt with this exact issue many times. The guy garanteed his tap was the exact fit for this fitting. Its basically a pipe fitting - drumroll -

1/2" and 14 TPI threads.

Of course he reamed me on the cost - $21.00 for a single tap. Write it off to consulting fee.

30 minutes of sweat and a little canola oil on the tap cleaned the threads beautifully. Sucked the rest of the junk out with a narrow nozzle on the shop vac. Flush down through the hole with the garden hose and with the block plug open to get any remaining shards out. A little teflon tape and new coolant and no more leaks. So far.

[Ketch]

P.S. This question of where to find the block plug.

There is a sensor with some wires attached with a grey connector on the right underside of the block. It must be the coolant temp sensor. Pull off the connector and back out the whole thing with a socket. Move out of the way or you'll be drinking Dexcool.

[IdahoRodeo]

Any chance you can give me the dealers name and number. I am going through the same thing and would like the steel connector as well. Everyone around here is only stocking the pot metal junk. Thanks

[Mr. Smith]

Originally Posted by Ketch

Such a shame. We have just 60,000 miles on this (a 1999 Suburban LT 5.7L) and this is just one of a string of problems related to cheap materials and poor quality. I may never buy another GM product again after this. GM, I hope you are listening.

Go buy a Ford or Dodge since this petty thing turns you away. You thought you had it bad with this POS fitting...

I mean really...you are right it could have been designed better. They make an updated piece made of steel thats good. Aftermarket has had steel for a while now.

There isn't one manufacturer that doesn't make mistakes and this won't be the last. FIx it and move on. Enjoy your truck life is to darn short.

[Pats1999]

FYI, Advance Auto's have a Dorman brand replacement fitting. It's much heavier and better built that the GM piece of crap. Cost $12.

Pat

[Elbert]

Originally Posted by EdH

What's a good way to fix a leak where the heater hose connects to the intake manifold? Had it to dealer once (and last time), but it started leaking again. Is there a replacement for the funky leak prone connector?

well I fixed mine. I used the old style type heater host fitting (bought one made out of stainless steel) and I replaced that crappy molded heater hose with just plain "regular" heater hose. I did double wrap the heater hose hear the engine where the hose rubs. On my 92 K1500. Its been doing fine for over a year now.

My experience stated out with the connector leaking and then turned into the connector and hose need replacing. I decided not to do that and went back to the "old school" setup.