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Discussion Starter #1
Anyone ever ran the MLS on the early LS heads that had the notch on the mating surface and factory graffiti gaskets?
 

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Discussion Starter #2
Im about to be doing this I believe
I’d hold off on that lol.

Been having a super small coolant leak since week one of install. It’s been about a year and now it’s leaving spots. Pretty sure the deck on these older heads don’t work without milling to use MLS.

The heads look like early Fbody heads. I remember reading about it way back in the day, but can’t track down a forsure answer.
 

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Discussion Starter #3
Lol summit sells the right gasket, you used the mls gasket for post 2002 heads and now its leaking coolant...
Yes but Iv done it many of times on post 02 heads that had the graffiti gaskets, and they worked fine.

But none with the notch..... Iv never seen the notch on truck heads.
 

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Discussion Starter #4
Interesting

Im honestly not sure which I have, im assuming notched because its ab 01 5.3...

Curious tho, if I get an ARP stud kit, that isnt TTY anymore right? Would be nice to be able to retorque the heads.

I dont have milkshake, just a bit of steam getting into the oil and sludging it. If it was already mls and not tty I could retorque it and it would be fine.

BUT once a paper gasket leaks it usually cracks and lets shit by regardless of a retorque, and no way in hell do I want to risk it on tty bolts...
My 01 had non notched 862 with graphite gaskets. I ran LS1 MLS and factory TTY blots, never had an issue. I’m guessing the notch is super early 99 stuff, same time as the early odd fbody heads you never see anymore. because I’m not finding anything about them.

ARP is normal bolts/studs. No TTY or degrees.

But make sure your not just fighting 706 head problems.
 

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Discussion Starter #5
Yeah 706 are the heads that crack right?

Im hoping not that lol
Yea. Factory defect. It was technically just casetech “iPhone battery icon” 706s, but Iv yet to see a non casetech 706. And I still see them on motors in 2021, kinda amazing.

IMO, I’d rather know the cause of my failure, then have to figure out why. Head gaskets don’t just go out on LS motors.

But with the all the non 706 LS motors Iv worked on or owned, I can count on one hand how many had head gasket issues. 2 were pull outs that got hit so hard the gasket broke. R&R heads and gaskets, but still rebuilt the heads and used on another motor. 2 were fleet trucks that keep boiling over coolant. Both had stop leak, and heads reused. And the 5th would be this POS.

About 50-100 LS motors Iv done with “headgasket” issues that were all just 706 problems.
 

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Discussion Starter #6
Do all the waterpumps for these have metal impellers or is there like one brand that is all metal? Im looking at GMB because a lot of people have said they had good luck with them, are they all metal?
I’m not sure. But I know GMB is that cheap brand on amazon. Iv used them before, and they work, but my god they will rust up all the hose connections in a month.

I’d just spend the extra $20/$30 and get a delco or Gates.
 

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Discussion Starter #7
But I found a set of notched heads in storage. 853 heads. As you can see by the condition of it, these early heads are not popular or even worth the time to clean.

873039


And I have bone stock 99 LS1 sitting on the ground.
873040


Notch is flush due to old style gasket. MLS won’t swell to cover it, or even seal there. So I guess I answered my own question.
 

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Discussion Starter #8
What do you mean "rust up the connections"?

Are you saying the worm clamps rust? Because I can buy better worm clamps at home depot lol.

Or are you saying the metal impeller is somehow more rust prone than the Gates pump?

Is the Gates also metal?

I figured metal to metal I dont see a difference till the black waterpumps on summit lol...
No. All the water necks on the pump. Pump will still look like brand new aluminum on the outside. But once you take all the rad and heater core lines off it’s scaled up rust all inside. Like SBC bad... on aluminum.

I doubt there’s any propeller change. And the factory unit goes for 200,xxx plus so I dont see a reason for a “upgrade”.
 

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Discussion Starter #9
The MLS gaskets for the notch heads have thicker rubber right there for the notch.

They are SPECIFICALLY and upfit part to run an mls gasket where a graphite gasket came stock.

Would you like me to find the part number on summit? Ive seen them, I might need them lol...
Iv never seen another set of 862 or any truck head with the notch.
 

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Discussion Starter #10
Thanks for the pics tho, I still need to take a look at my heads physically. Been researching everything else today. Money for all this stuff just cleared lol.
I should add this truck is a 99. Like baby blue interior, even blue headliner, Manual height adjustment on the seats, a lot of odd stuff going on. Super earlier NBS truck.
 

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Discussion Starter #11
Would you like me to find the part number on summit? Ive seen them, I might need them lol...
I appreciate it, but I’m just putting 243s on it. 5.3 was already built, with gen IV rods and flat tops. Budget ran low so the 862s were reused.

If it says 706, 853, 241, i chunk them in the scrap pile. Just never figured out the reason for the notch until today.
 

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No. All the water necks on the pump. Pump will still look like brand new aluminum on the outside. But once you take all the rad and heater core lines off it’s scaled up rust all inside. Like SBC bad... on aluminum.

I doubt there’s any propeller change. And the factory unit goes for 200,xxx plus so I dont see a reason for a “upgrade”.
Maybe something else was going on on the truck? Aluminum doesnt rust? If its the same materials why would it rust because of the brand alone?
 

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Broke a waterpump bolt off smfh, nobody told me they were tty, I should have seen it in the design.

Oh well, buying a drill. Stainless stud kit is on the way for it. Best part of studs is when you find yourself drilling out a snapped bolt lol...
 

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Should I tap it?

Always done studs into a drilled out mess on aluminum. There I just drill the hole a smidge small, put jbweld on the stud, and crank it in. Will this work on an iron block? The studs are aircraft stainless, but maybe softer than the block? you're experienced enough what say ye??
 

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Broke a waterpump bolt off smfh, nobody told me they were tty, I should have seen it in the design.

Oh well, buying a drill. Stainless stud kit is on the way for it. Best part of studs is when you find yourself drilling out a snapped bolt lol...
wat, water pump bolts are not tty? They're like 22ft lbs.. how did you break that?

Just use a center drill to spot the bolt, drill and use a ez out, or a left hand drill. That will back the bolt out unless you bottomed it out and galled the threads up / cross threaded it or something.

But again, what do I know.. I'm just a dumb machinist

The more I read your posts the more I think you should not be working on these motors.
 
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