Waterpump Surface Prep

[Fitz98]

98 Expedition 5.4.
I cleaned the water pump surface in preparation for a new pump install. First wire brush, then green scotchbrite pad. Came really clean, but there are some areas of slight oxidation remaining as seen in the picture below.
Is this anything to be concerned about, or should this be no problem with leaking? O-ring seal on the water pump.
I am debating on a light coat of Hylotyte red on the surface to bridge some of the imperfections, although that might make installation of the o-ring bind with the added friction. Also thinking a Dremel polish as well, but that might do more harm than good

 

[oldhp]

A light coat of Right Stuff around the flange where pump o-ring goes and bolt the pump on. Let it sit over night and try it would be my idea.

 

[Snagglefoot]

Just to clarify, are you planning on reusing your old water pump?

 

[Fitz98]

Originally Posted by Snagglefoot
Just to clarify, are you planning on reusing your old water pump?

No, it is new with a new O-ring

 

[Fitz98]

BTW the surface preparation I am referring to is the block mounting surface that the o-ring of the pump will seat against.

 

[Trav]

This is a job perfectly suited for Hylomar, the blue M or the red will do the trick. Do not remove to much material getting rid of the corrosion spots.

 

[WyrTwister]

I would use the o-ring and , at the very most , apply a light layer of grease to the mating surface . The grease is probably not necessary . Just if it makes you feel better .

 

[mk378]

Where the o-ring touches is the only place that matters, and it is rather pitted. Do not put this sort of sliding o-ring seal together dry-- in a water system use silicone grease. Compounds that are intended as "sealer" may have a slight advantage over plain grease.

 

[shibby6600]

Originally Posted by mk378
Where the o-ring touches is the only place that matters, and it is rather pitted. Do not put this sort of sliding o-ring seal together dry-- in a water system use silicone grease. Compounds that are intended as "sealer" may have a slight advantage over plain grease.

Specifically, use a grease meant for water systems that withstands high temperatures. You can find them at your hardware store.

 

[GMBoy]

Nice to see your attention to detail.

I've dealt with similar situations. I just wiped a film of permatex blue gasket maker on the surface and installed. I think the gasket maker filled in the imperfections enough that the 0-ring was able to seal well. Never had any issues or comebacks.

 

[The Critic]

Originally Posted by GMBoy
Nice to see your attention to detail.

I've dealt with similar situations. I just wiped a film of permatex blue gasket maker on the surface and installed. I think the gasket maker filled in the imperfections enough that the 0-ring was able to seal well. Never had any issues or comebacks.

Except the next guy will need to deal with a RTV mess like this one.

 

[Fitz98]

Consulted with Hylomar. Their recommendation was Hylotyte red (Which is designed more for water and glycol based systems) Dilute with Acetone and brush a thin film on surface to fill imperfections. Allow solvents to evaporate and assemble. I went 1 step further and skimmed a sharp blade along the surface to leave material in the voids and a very thin film on the rest. The small red ring on the inside surface is where the o-ring seats

 

[Trav]

Originally Posted by The Critic
Originally Posted by GMBoy
Nice to see your attention to detail.

I've dealt with similar situations. I just wiped a film of permatex blue gasket maker on the surface and installed. I think the gasket maker filled in the imperfections enough that the 0-ring was able to seal well. Never had any issues or comebacks.

Except the next guy will need to deal with a RTV mess like this one.


Tell me about it, I just did a valve cover on a ecotech that someone went over the top with the stuff on both large rubber gaskets. It failed and leaked (no surprise) and I had to dig strings of that stuff out off all sorts of places and crevices.

 

[GMBoy]

Originally Posted by The Critic
Originally Posted by GMBoy
Nice to see your attention to detail.

I've dealt with similar situations. I just wiped a film of permatex blue gasket maker on the surface and installed. I think the gasket maker filled in the imperfections enough that the 0-ring was able to seal well. Never had any issues or comebacks.

Except the next guy will need to deal with a RTV mess like this one.



Not like that...I mean just a skim coat. Wipe a film on the surface, not a bead or any large amount.

 

[GMBoy]

Originally Posted by Trav
Originally Posted by The Critic
Originally Posted by GMBoy
Nice to see your attention to detail.

I've dealt with similar situations. I just wiped a film of permatex blue gasket maker on the surface and installed. I think the gasket maker filled in the imperfections enough that the 0-ring was able to seal well. Never had any issues or comebacks.

Except the next guy will need to deal with a RTV mess like this one.


Tell me about it, I just did a valve cover on a ecotech that someone went over the top with the stuff on both large rubber gaskets. It failed and leaked (no surprise) and I had to dig strings of that stuff out off all sorts of places and crevices.



Just a skim coat is what I meant - not a lot and not a bead. Talking a pea size amount on my finger and coating the surface. No harm at all to the next guy.

 

[bdcardinal]

Originally Posted by GMBoy
Just a skim coat is what I meant - not a lot and not a bead. Talking a pea size amount on my finger and coating the surface. No harm at all to the next guy.


That would be ok, and to most normal people explaining it like that would be all that is needed. Unfortunately for some people they read that and put an entire bottle of RTV on one part.

I know some techs who say for o-rings that if it touches water/coolant to lube it with dielectric grease and if it touches oil/atf to use TransGel.

 

[nthach]

For me, a small bit of Dow 111 or dielectric grease is what I use for O-rings that are in the water path. Grease or Vaseline for oil ones. Good old soap and water does the trick for water crossover O-rings on Toyota engines. I'm in the school that RTV should not touch O-rings or gaskets, unless it's used on seams or corners, like on Japanese engines.

Originally Posted by bdcardinal


I know some techs who say for o-rings that if it touches water/coolant to lube it with dielectric grease and if it touches oil/atf to use TransGel.

When I was at The Critic's shop doing an on-car reseal of the steering rack for my parents, I used TransGel to lube the O-ring and seal on the rack's right side bushing. That stuff is almost like hair gel, it's stiff but pliable.

 

[Fitz98]

I had a similar issue on my transmission pan gasket. The previous transmission service that was done by someone else had some sort of stringy, melted gummy residue around the perimeter of the seal. Foolishly, I only cleaned one surface before re-installing it and sure enough it leaked on the surface I did not remove the old sealant from.
With that being said, I think the biggest factor is using compatible products for the application. In the case of the transmission, the sealant used, clearly was not compatible with or resistant to transmission fluid.
So far, my experience with Hylomar blue for fuel and oil and Hylotyte red for water and glycol has been a good one and a thin film. Time will tell as I put the vehicle back in service.
Hylomar also suggests using this as a gasket enhancer, or for filling in voids or corrosion pits before gasket installation, as is the case with my water pump and around coolant ports on my intake

Hylomar Video