I would machine the housing if you have that much interference. Basically you are trying to seal two "perfectly flat" surfaces but for the fact there is a bulge being created by the thermostat sticking up too far. I just looked at the Motored (Stant) thermostat for the 302 and it measure 1.75mm at the flange thickness and is 54.1mm diameter. What a PITA for sure!
Need cooling help please
- Thread starter SpyderMike
- Start date
I measured the depth for the thermostat on one of my housings, I had .98mm and the thermostat was flush with the sealing surface.
I'd RTV the thermostat to the housing and let set up before assembly so thermostat does not drop between housing and intake.
I'd RTV the thermostat to the housing and let set up before assembly so thermostat does not drop between housing and intake.
I agree that machining would be the best solution if possible at this point. Note that the mounting flange varies in thickness too. How does one machine this thing down the correct amount?
I will be tacking the thermostat down - great suggestion!
I mean the previous install was just sealant without a gasket...it lastest 18+ years. Hmmm
I will be tacking the thermostat down - great suggestion!
I mean the previous install was just sealant without a gasket...it lastest 18+ years. Hmmm
If when you installed this most recent time you had significant leakage, it is more likely the thermostat slipped out of the housing and created the gap. As for machining, you would need someone with a CNC mill. I still never heard how you determined there was a major leak? How was that done - with the vacuum system?
When I pulled it back apart, the gasket still held the thermostat in the housing because I had thin coated both sides (per your suggestion); the thermostat was not displaced.
I pressure tested and could hear and feel the air coming out of a specific location (along the outboard bolt side).
I pressure tested and could hear and feel the air coming out of a specific location (along the outboard bolt side).
The hole in the thermostat gasket is smaller in diameter than the thermostat flange. Therefore the gasket rests on top of the thermostat flange. If that flange is above the housing surface, then the gap in space results in reduced gasket adherence and coverage. It was leaking where the thermostat flange was protruding the most to the minimal recess in the housing in that area. That is my guess....
Man, I will be happy when this simple task is resolved!
Man, I will be happy when this simple task is resolved!
I live in Ohio and am willing to throw the housing on my cnc mill for ya and take it down flush. Just would prefer to have the thermostat as well to measure for correct fit for you.
I'd even run a few test cuts on scrap before screwing up lol.
How can I not take you up on this most generous offer!? Please DM me your address and I will get it out to you. Thank you in advance!
Mike, I found a few issues the the water neck after receiving it and I will dree is up for you. I have attached some pictures below. You will see why it leaked.
One side sits flush, where the other is not, it was machined out of true.
You can spin the thermostat and these points stay the same, so it is not the thermostat out of wack.
I also noted several deep / scratches on the surface, you could catch your finger nails in them, they ran from the thermostat ring to the perimeter of the part.
I also blued the part and lapped it on a surface block. It isnt flat. I will true that up with a few thousandths off it.
I should have it cleaned up this weekend.
One side sits flush, where the other is not, it was machined out of true.
You can spin the thermostat and these points stay the same, so it is not the thermostat out of wack.
I also noted several deep / scratches on the surface, you could catch your finger nails in them, they ran from the thermostat ring to the perimeter of the part.
I also blued the part and lapped it on a surface block. It isnt flat. I will true that up with a few thousandths off it.
I should have it cleaned up this weekend.
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Wow, what great work Douglas. How do you plan to deepen the recess?
Once the surface is trued, I will manually do that on the cnc mill. I will just make a spiraling circle cut to ever so deepen the areas few thousandths at a time and test fit it till it is flush. The circle part I will program. The fun part will be stabilizing it on the mill. As it is awkward to support.
That sounds very cool. Keep posting the results!
I can't thank you enough Douglas! Simply amazing.
I am off to Amsterdam and back on the 21st.
I was in the area and stopped by to see one Hillbank had in their parts stock. These are made at the factory. It was in worse condition. I will post pics. Folks, if you have a recent SPF that you are putting together, definitely inspect this part!
I am off to Amsterdam and back on the 21st.
I was in the area and stopped by to see one Hillbank had in their parts stock. These are made at the factory. It was in worse condition. I will post pics. Folks, if you have a recent SPF that you are putting together, definitely inspect this part!
The large outlet tube had been machined down until there were two small holes in it. It also had a deep groove along that tube.
I opened up some pitting when i took a few thousandths off the surface, on the edge of the recessed area. Nothing I would worry about. There is about the same amount of a gap around the thermostat as before, I think that could be a good location to add a thin layer of RTV to act as an oring around it under the gasket.
Deburred and gave a light polish. Lol
Yours also has that sharp edge in the bend from yhe two tubes welded together. Not anywhere near as bad as the one you posted, but I would file it down when you get it back to help clean up the flow of fluids.
Deburred and gave a light polish. Lol
Yours also has that sharp edge in the bend from yhe two tubes welded together. Not anywhere near as bad as the one you posted, but I would file it down when you get it back to help clean up the flow of fluids.
Nicely done
Lovely! I am very thankful for your efforts Douglas! I am also excited to give it a go once I get back.
