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Well she runs GREAT![cl i TOOK HER FOR A COUPLE "SHAKE DOWN" RUNS.No issues. Today while backing into my brother`s shop I hit one of his racecar trailers with the sidewall of my BFG www destroying it. Anyone have a BFG www they want to sell? The problem is they no longer produce 285 70 15`s:mad:
 
NEW ISSUE..........:rolleyes:My "expansion tank" will not hold pressure especially when it`s cold. The tank itself is good,it blows by the rad cap like it`s not sealing. I changed the cap and measured the distance to the cap seat and it`s the same as any radiator.I have it plumbed direct to the engine in two different places. Could there be possibly be more pressure at the engine? I`m running a 16 lb cap on both the tank and the radiator. It also seems to stop once the engine gets up to temp. The main problem is, is that it does not suck the expelled coolant back in as it cools. Her`s some pix of it.:confused:
 

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Well, I think I now know why the guy at the swap meet was selling that "expansion" tank. The filler neck wont seal. I tried putting a spacer washer in the filler(on the tank)I could feel that the rubber seal was seating on something because it took more effort to push the cap down to then turn it into lock position. I then started it up and reved it a little and the coolant blew right past the cap:mad: After I replaced the water pump I removed the "expansion" tank,hoses,brackets and the catch can.I plugged the smaller connection and piped in a bleeder valve in the 1/2" hole.I opened the bleeder and started filling the radiator until coolant started coming out the valve. I closed the valve and continued filling the radiator. When it was full I started the engine,the coolant dissappeared, I continued to fill it as it ran,once it got up to temperature and no more bubbles were coming out,I put the cap on and turned the cooling fan on. She stayed right at 190 deg. I took it for a short ride and the temp never came up.I think my cooling issues are over.[cl
 
Well, This thing seems to be real tempermental:confused: Today I drove it about 18 miles to show some fellow motorheads my creation. Before I left I checked the level in the overflow. It was empty, so I overfilled it thinking I would possibly compensate for a little leak in my bleeder valve. I left and about halfway there I had to climb a hill about a mile long. As I was going up the hill the temp kept rising, when it got to 240 and I was at the top, I pulled it over and let it cool down for about 5min. She was bubbling out of the overflow.When it stopped overflowing and cooled a bit, I continued.I let it coast down the other side of the hill and it cooled right down and I made it the rest of the way with no overheating.[cl:mad::confused:
 
Just looking at your pics and a couple things jumped out at me. I read that you've already tossed the expansion tank so this may not matter but where the hose on the left side of the engine was connected is only used for temp sensors - can't see where the smaller hose is connected on the right side, but neither of those locations are high enough to properly bleed out air. They are more likely to disrupt coolant flow. These engines only had one heater hose outlet - on the rear of the passenger side head, the return was to the top tank of the rad, and drawing flow anywhere else could mess with things.
An expansion tank would probably work better if it was plumbed directly into the flow from the upper rad hose, kinda like the early 60's full size Fords.

Do you have a build thread on your car to satisfy our picture drooling needs??

Maybe I'm behind the 8 ball but it looks as though you're running the rad in the back?? If so, lots of other things could be contributing to your problem - flow restrictions, rad size, fan CFM, air flow, etc.

Pics, we need more pics, pleez... [P
 
ZZ,The only pix I have showing my hookup is on the 8/12 post. This engine is the 472 from a `69 Coupe Deville. The heater hose conn was where I have the small conn. just below the thermostat. The hose conn to the head,you mentioned,was like that on my on my 425.I truly believe there was something wrong with my exp. tank because the radiator cap would not seal. I think I worked out all the "bugs" in the system. I changed the leaking bleeder and extended the outlet above the highet point of the cooling system and took it for a 1 1/2 hour drive last Sunday with no overheating[cl
 
Thanks ZZ,BTW been following your 34 Caddy build,that thing is sweet!![P[clWaiting for the latest pix. It`s gotta be nearly done by now.
 
Well, IT OVERHEATED AGAIN!! The same hill as the last time it overheated:mad::confused: My next trial will be a thicker/larger radiator:confused: Maybe back to the expansion tank with a higher pressure cap:confused:Any other ideas out there?:rolleyes:
 
Any possibility that under high flow

That you have a hose collapsing?? You'd think the pressure will keep it open but I've seen it happen with high flow water pumps and wimpy hoses before....13 to 15 lbs is not a lot of pressure and the suction side can suck a weak or non reinforcement hose shut shut down or greatly reduce flow to the point of overheating..... Just a thought....
 
Haven`t been on here in a couple weeks. Just noticed your response Sarge. All the hoses appear to be OK.With the cooler weather in our area she runs cooler (abt 200 deg). The last time I had it out and it started to get hot, (temp outside abt 80deg.)I removed the cover over the radiator.The whole inside of the car heated right up and the temp went down to 200 deg.When outside temp cooled down, I put cover back on and it stayed at 200.From this I conclude that maybe I have air circulation problems.:confused:I may try running it for a while without the trunklid.[S
 

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