nailhead overheating...HELP! ive reached wits end!

So do Edelbrock carburetors but they are both WRONG for the street!
Listen to C9!

 

So the factory setup was wrong? Ran them on the street fine. I'm wondering why now. The factory stuff runs great. I put the MSD and the Edelbrock carb on mine and it's ported vacuum. Runs fine.

 

Here's where that comes from.

GM developed the ported vacuum system and I understand licensed it to other manufacturers.

It is designed to make the engine run hot - for better nox capabilities I believe - and hold emissions down.

That's what the thermostatic switch at the back of the late BB Buicks is for.
As well as other GM engines.

The advance system is connected to the thermostatic switch which feeds ported vacuum to the distributor until a high engine temp is reached then the thermostatic switch swaps to manifold vacuum which allows the distributors vacuum advance to advance until the engine cools down.

Then the cycle starts all over again.

More than likely MSD wrote their instructions as a sop for the EPA and the like.
Same with Edelbrock as the good doctor noted.



I have a write-up by - I think - a GM engineer that's a little more extensive that I can post, but pretty much the same as what I wrote except for where he calls it an abortion and I don't.

I have other names for the system....

 

check your rad cap and make sure the seal ring is seating on the rad lip. I went through all you have only to find the parts house gave me the wrong rad cap. only takes a second to check

 

lol, I actually asked about it when I ordered the distributor, since I was used to doing the manifold vacuum on other engines. I was told the curve was different. Might have been bullshit. But then again I've had it on there both ways without it really making a difference that I could tell. Maybe I need to investigate it further.

I remember those thermostatic switches, lol...

 

Agreed. But without the shroud, and no hood, the air will just take the path of least resistance, which is bouncing off the radiator and out the side rather than THROUGH the radiator.

However... it does sound like you've got other internal problems and the shroud wouldn't make as big of a difference as you're seeing.

 

Sounds like a blown head gasket/cracked heat/&-or, to me, shouldn't be 'losing a lot of coolant' at 210f, if that's an accurate indication of the actual temp.

 

Funny thing is the stock gauge on my 57 shows just under the N at about 210.

 

I'm tellin' ya, put a big nut in the lower radiator hose to slow down the coolant. We went through this on that roadster with a 425. Its worth a try.

We tried all kinds of different stuff with that car.
Shroud with mechanical fan, added an electric fan, sleeved the lower hose cus we thought it was pinching, tried a bunch of thermostat/empty housing combos, recurved the dist., the main problem was that the coolant was moving too fast.

 

which water pump were you running A/C or non A/C? the A/C pumps seem to have a problem with doing that for some reason. 5 blades instead of 3.

 

I can't remember. I don't know if I even had the water pump off.

 

Well, I checked the temp with a thermometer and the water was just a little warmer than the guage. Iwent to the pet-cocks on the block and was able to get one out. A little brown water came out so I poked it with a screwdriver and then it came gushing out! Brown, almost mud with little chunks of rust. So I'm thinking I've got to get this sludge out. Does anybody know of a flush or anything else that will get it circulating so I can get it out? Maybe I need to take it somewhere? Thanks

 

can you post the link to the pressure flusher tech thread? I searched and couldnt find it. Thanks.

 

any of the later guys have a link to this thread? Thanks!

 

Did u have the block check done yet? Most radiator shops will do it for little or no cost. Do this first! Two other things, I don't recall how the Nailhead cooling system is bypassed (around thermostat). But this would cause the engine to overheat during warmup, but this would not happen if no thermostat installed.

Lastly, get one of those Prestone flush kits and put that in at the heater hose. Hook a garden hose to it and flush while engine is cold (garbage goes back up the radiator and out), then leave the hose running and start the engine and let the remaining rust flush out of the radiator. See what happens.

 

I just went through the same issue with my '58 364. Turns out ALL temp senders now are 220 degrees and meant to be installed in the radiator, which gets hot faster than the block will. As you probably already know, you have 2 options in the block to install a fan switch, at either the front or back of the block. If your block gets to 220 degrees, it's already too hot! I special ordered a 180 degree sending unit from a local rebuilding shop and installed it in the front boss. It now turns my fan on before I start blowing out hoses! Hope this helps.

 

I found out that I had a terrible sludge problen with my 322. It was a low milage engine (18,000 Mi.) and had silted up sitting around in someones garage for 40 years. By chance, I poked around with a screw driver thru the drain plug hole and had the same results as el canejo above, solid gunk in the bottom of the block. Luckly, I was about to do a valve job so later with the heads off I started digging around down through the coolant holes into the water jacket of the block and then using a small nozzle on a garden hose to blast down inside the block. I got almost a solid bucket full of brown sludge out of the bottom of that block.
Of course, the best way is to break the engine down and vat the block but it can be done in the car if you are careful. Just my experience, don't know if it can work for you.

 

You've got at least two problems, besides the sludge thing. No shroud, elec. fan in front the radiator. All bad. 190 degree 'stat, timing, have the radiator rodded out, and see if those help. I finally added a second radiator under the floor over the rear axle, my problem was more coolant in the engine than the teeny tiney Mustang radiator. All better now!

 

I thought I had an overheating problem with my 65 Riviera with a 401, so I installed a temperature gauge, installing the sending unit where the warning light sensor was installed, in the front of the engine above #1 cylinder. The gauge read about 185-195 after warming up at city speeds. Above 50, it started rising to about 210, where where I panicked and got it home. Everyone that I had read said that their nailhead ran between 160-180 deg no matter the speed or temperature. I'd like to know where they mounted the gauge sensor.

I checked the 1965 Buick Shop Manual, and it said the sending switch would indicate cold below 110 deg, and hot above 245 deg. I figure that if the factory engineers didn't worry about the temperature below 245 deg, why should I? Does this sound reasonable?

 

Did you even think to look at how old this thread was before posting ??

 

Did you look to see if what he posted was relevant? It is, so get over it.

 

LOL Yes boss whatever you say

 

You must be one helluva welding instructor if you treat people who ask questions that way.


Notice the dripping sarcasm.

 

I have no issues with them getting to 210-215 some just seem to run there. My '57's stock temp gauge reads about 210 or so smack dab in the middle.

 

I wasn't responding to your question, but rather your "get over it"

Lighten up, smile a little your day will be a lot better.

I guess old threads do have some life and info after all. Just like some old farts

Don't get all crabby on me now.