Technical Blowing water pump gaskets on a SBC

First, is that a reverse rotation pump? That setup requires one.
Second as others said way way too much of that blue **** on the gaskets the first go. Plus it never seals right on anything unless you give it proper time to cure.
That said, add me to the #2 Permatex brigade on gasket sealer for any water outlet.
It appears that there is clearance between the bolt heads on the back of the pump and the timing cover but is there clearance on all of them?

Other than that, I am rather on the line with the others in that those extremely long bolts that are needed with that belt setup may not be doing the job that they need to do. Every stock GM setup normally uses a bolt with a stud sticking out past the head for mounting an accessory. Meaning that the bolt is torqued against the water pump and the accessory is bolted to the stud sticking out on the bolt.

 

I've never noticed, but do stock mounting bolts have a full diameter sized body, with just the required amount of threads rolled into the engagement length? (in other words, bolt body diameter is a closer fit in the water pump body holes) If so, it's possible that the bolts supplied in the kit have a longer thread length, which allows the pump body to rotate and flex. Just thought...

 

Only happened once to me (SBC motors since 1962), aluminum pump , dry gasket install, 6000 rpm , loosened the cap & made it home (10 miles) used permatex on new gaskets , no sweat since . I wrote it off to me not snugging up the pump bolts .

 

The blue stuff is the dry felpro gasket. There is absolutely no sealant. The water pump is a reverse flow along with the fan and fan clutch.

 

Easy enough to test the cap with a adapter for a cooling system pressure test kit/pump.

 

We are not running the byp*** hose. The water pump is aluminum. I did find this gasket at Summit racing. Read the reviews.
https://www.summitracing.com/parts/...MIx8Oq3Y_-8AIVrAutBh1Wdw**EAQYBCABEgK7IPD_BwE

 

Way to much **** hanging on those 4 bolts .
Fix that & your gaskets will stop failing . . . . . . .

 

I should have submitted this for tech week.
How to use blue RTV.
Step one.

step two:
Always refer to step one.

 

Odd that we ran the engine 2800-3000rpm for 30 min and had no leaks. Temp did get to 220F because the shroud was off. I spoke with a felpro tech and he was clueless. Never heard of such a thing. He told me to try another manufacturers gasket. Also talk to the owner of CVF pulleys systems. He sending us another pump no charge. My view is the gasket yield due to pressure. Seems the hard throttle created a max pressure. I’m getting a Cometic gasket which is a high pressure composite gasket. Though the sbc has a internal pressure byp*** we may drill a 1/8 byp*** hole in the thermostat or install a byp*** from the water pump to the manifold. The bolting is not the issue nor is the load on the aluminum bracket. I did use my past engineering skill set to calculate the load stress on the bolts and water pump to block flange surface. The tensile strength of all four bolts exceed the actual load stress. The bolt temps don’t go over 250F . So yielding to temp is not an issue.

 

The photo is not blue Rtv . That’s the BLUE FELPRO GASKET without anything..

 

Ok. The instructions are the same for that as well.

 

The longer the bolt, the more the length will expand with a given temp increase. They might be relaxing enough to allow coolant pressure to blow the gaskets. Is that's the case, then special bolt/studs with heads at the WP, as mentioned by others, might solve the problem.

 

looks like the bolts ride inside aluminum spacers, which expand more per degree temp rise than steel does. I doubt this is the problem.

I wonder how the pressure on the gasket due to the pump being pushed against the block by the drive ***embly compares with the pressure from the coolant. My guess is that there is a hell of a lot more than 16 psi squishing the gaskets flat.

 

***uming the pump mounts are flat and the gaskets are of good material, I can't see a valid reason for the gaskets to self destruct. Has me wondering if they are being destroyed by cavitation. Running for an extended period of time with air in the system would likely contribute to that.

 

Its not traditional

 

I doubt Cooling system pressure is the cause.
I've had air compressor failures fill the cooling system with air pressure and lots of things fail(hoses, radiators heater cores etc) but no gaskets.

 

It not the " tensile strength " of the bolts !
There is just too much stuff hanging on them !
disconnect everything & put a standard pump on it with just a belt running the pump ,
I'll bet you it will run all day with no gasket problems .
Put more mounts on your accessory drive system to other locations on the engine block . and I'll wager your gasket problem will be solved .

 

I wish I could ditch this pulley system. It’s not my truck. Doing all this work for a buddy. My money is on the pressure limits of the gasket . Remembering my old pipeline days the flange gaskets did yield when over pressured. We were dealing with pressures at 720-2000psi. The mount loading on the pulley bolts based on the yield and tensile strength is over 9800 lbs.
That’s each bolt . If there were only two or three bolts holding this pulley system I would see the load not being balanced.

 

HE is not listening let him find out the hard way

 

I’ve seen pressure high enough to swell the hoses,,,,,but still not bother the gaskets !
Oh well,,,,,you’ll figure it out ,,,,,,and besides,,,,like you said,,,,it’s not even your truck .

Keep in mind,,,,sometimes these aftermarket add on drive systems can cause severe headaches,,,,,,for the mechanics.

Good luck .

Tommy

 

Throwing my thoughts into the fray.

What dictates the correct torque setting of the bolt is diameter, grade, and coating.
Diameter is a given, can't really change that. Grade and coatings can change.
Higher grades will require a higher torque setting to properly stretch the bolt to yield strength for effective clamp load.
Coatings or platings may require more or less torque to reach yield strength.
Lubricated threads will reduce the required torque t reach yield strength.

If the torque setting for the bolt is too high or too low then the clamp load provided by the bolt will be insufficient. Bolts act as springs, if the spring is over tensioned the bolt will stretch and lose clamp load, if the bolt is under tensioned it will not provide enough clamp load and the bolts themselves may loosen.

A proper nut/bolt connection will use washers to spread the load evenly and prevent damage or pulling through.

Bolt head shape/type can also affect how well a bolt will be able to clamp.
Typical 6 point bolt head usually has a large surface area and a good bearing surface to apply the clamp load from the bolt to the component it is clamping.
12pt head bolts will have a smaller head(about the same diameter as the shank) with an integral flange, which allows for a good bearing surface while reducing the need for more room for an unnecessarily large socket(like a 6 pt).
Allen head bolts are good for tight areas, but most have a very limited bearing surface. Usually rounded corners and even with a washer can often just dig into the washer and cone it. Not the best for high torque loads as they will wallow or gall the surface and not provide correct torque load. But lots of components use these bolts because 'looks cool man'. You will reach the 'torque spec' but you have not reached the correct yield strength as the torque you are applying is not tensioning the bolt just merely the friction of grinding the bolt head into the component is giving you a false reading.

Verify there is no paint or powder coat on the bolted surfaces.
Verify the mating surfaces are true and flat.
Verify the spacers are the correct lengths for their positions, or if all the same height that the WP sleeves are mounted on the same plane. Also anything over an inch, I prefer to just use steel or stainless as the longer the distance the more likely you can cause the spacer to wallow around if it does not have a triangulated stiffener.
Verify the main bracket is square and true.

My opinion on the drive system is that it is not providing a constant or correct clamp load to the block and is not triangulated to prevent movement.
If it was merely the Alt and tensioner mounted to the bracket, it might be fine.
But there is the PS pump attached as well, which will add not just weight but quite a bit of load to the drive system when the steering wheel is turned. This will try to twist/rotate the bracket ***embly. All PS pump systems usually have the pump bolted to the front and side of the engine block. Look at stock systems, they have about 10lbs of steel bracektry holding them on.
Not to mention the fan ***embly is pulling the pump forward at speed.

There is no way the system water pressure will blow out the gaskets while not affecting the hoses.
That's not gonna happen unless the block and WP do not have flat surfaces or there is an insufficient clamp load to the water pump mount.

To me it looks like the water pump gaskets are getting walked out until they eventually leak and fail due to incorrect clamp load on the whole ***embly.

Albeit, with the ***embly bolted together as is, you can grab either side and get it to clock a little bit either way. Relying on just those four bolts on those long spacers without any triangulation is your problem. Since you cannot increase bolt diameter you will need to have some kind of stiffener to triangulate the bracket. If the bolts used are Allen headed, they do not provide enough even clamp load and act more like a spherical bearing allowing the ***embly to rock.

TL;DR
Not enough kids played with Tinker-Toys.

 

OK , just keep blaming it the bolts & gaskets .
I see you seem to have ruled out that a belt driven , multiple accessory system , hanging on 4 bolts designed to hold a water pump , could be the problem .
Good luck .

 

I would suspect there is something going on with that belt system. Just because it is the only different thing on the system. You should be popping hoses before pushing out gaskets if it was a pressure thing. If the guy is dead set on using that system get a bit of copper sheet and make a couple gaskets. If it is because of the belt system you might be able to see what is happening because it should take more time to happen.