Phenolic spacer recommendation for 52, 331, Rochester 4.

[52Cadillac]

Trying to cure my everlasting slow overheat problem in traffic, and occasional missing. There seems to be plenty spacers on eBay, but which one? And what thickness?
Thanks, Mike

[Dave Shepherd]

1/2"should do it, make sure all the linkages and choke tube work when done, also how will this affect the engine running hot, I assume this is to insulate the carb.

[52Cadillac]

It is to insulate carb. Also fuel lines to be insulated. But part of the process, not the cure.

[John Washburn CLC 1067 Sadly deceased.]

The one on e-bay that says:

Carter WCFB Small Bolt Pattern, Heat Stopper, Phenolic... It will work with Carter or Rochester.

jw

[52Cadillac]

Thanks John, will do.

[Caddy Wizard]

Electric fuel pump full-time is the car's salvation.  Trust me...

[Raymond919]

Hello Tim,
I had a hot restart problem. Not exactly like yours but with similar consequences. The car would not start again if it had been turned off while hot until it cooled a bit. I also once had a stall problem in very hot weather like you. That time I turned on the electric fuel pump and the car started right up. I don't leave it always turned on.

For the hot start problem I installed a 1/4 inch phenolic spacer. It was very reasonable in cost and included longer stud bolts to screw into the intake manifold and additional carburetor-to-manifold gaskets. I also replaced the intake gaskets (between the intake manifold and head) with new ones which didn't have the openings for the exhaust cross-over. I got them from Olson's. This prevented the heat from crossing over under the carburetor keeping it a bit cooler. I then eliminated the heat riser valve to prevent exhaust heat from being pushed back when the engine was cold since these can freeze up and over-heat the engine after the engine has reached operating temperature. All my heat problems were solved. I got my inspiration and guidance from John Washburn's articles.

You might want to check if your car was originally equipped with asbestos heat-wrap on the exhaust pipe near the connection to the exhaust manifold. New wrap will eliminate some engine heat under the hood. Safe non-asbestos replacements are available. Lastly, wrap the fuel line to insulate it from heat in the engine compartment.
Ray

[52Cadillac]

Thanks for the replies. I have an elec fuel pump in place. My car is a creep, when it comes to overheating. Temp creeps up in slow to no moving traffic. I've had this ongoing problem since I purchased car last year. Radiator has been out and professionally cleaned, thermostat replaced. Block flushed. I think I may have to try to have an extra core or two added to my Radiator if possible. Any other ideas Gents?

Raymond what did you use to insulate your fuel lines?

[Raymond919]

Actually, I haven't as yet insulated the fuel line nor the exhaust manifold. I also haven't yet insulated the heat pipe from the exhaust box on the exhaust manifold to the automatic choke. I plan to do so, however. I see the insulation available from companies like McVey. The car is running great without it but I wanted to make it be more authentic and by adding these additional steps, have an extra measure of protection against the heat.

[52Cadillac]

 I will have to check the heat riser gaskets to see if cut off, under the heads. Don't know if they were replaced. Heat riser has been removed From engine. Anyone have a part number for gaskets?

I belive this be the correct size for my carb. Can you confirm John.
http://www.ebay.com/itm/Small-WCFB-Carter-Phenolic-Carb-Insulator-Spacer-Holley-Teapot-Intake-Riser-Kit-/261113992427?pt=Vintage_Car_Truck_Parts_Accessories&hash=item3ccb9b54eb&vxp=mtr

[John Washburn CLC 1067 Sadly deceased.]

That would be the correct phenolic spacer. you can also get it in a thicker/taller version but this one should do the job.

John w

[wrench]

I was chasing a similar problem on another type of vehicle. Did all the usual stuff, timing, mixture,water wetter, all the cheap, easy stuff. Turned out to be a slight leak at the exhaust manifold donut was impinging on the block and heating it up in a localized area, eventually driving up the temp...

Just an idea...

[52Cadillac]

Ok guys, appreciate the help. Will order and tackle it along with some other problems to sort out. so youll be hearing from me lickity split. ha.  Thanks

[oldnick]

I'm willing to use and enjoy more my '51 Coupe which is fitted with a Rochester on the 331 and was planning to keep it as stock as possible (easily reversible mods preferred) as I need it as a reference to restore a '51 conv... I have eventually embarked in the following steps to fight vapor lock in preparation to the coming season:
- 12" push through fan on an thermostat off the left head outlet (on 180°f/off 165°f - first test with on 190°F/off 175°f appeared too high as the problem still occured), with on demand switch, at the right of the stock radiator support
- 1/2" carb phenolic insulator (hoping it won't mess the control rods operation)
- heat wrap protection of the incoming fuel pipes (stainless replacement of the stock one)
- heat wrap insulation of the headers (esp. left side)
- check if carb heating from header can be blocked

question: would it be recommended to make a thin phenolic insulator for the fuel pump itself (1mm or 2mm so as not to empede mechanical operation), as I suspect the heat of the block is mostly acting on the pump (vaporising fuel on the pumping stroke hence nothing to push afterward then carb starvation)?

[V63]

I would recommend an electric fuel
Pump especially if your area mandates blended (Ethanol) fuels. I prefer to run the electric with mechanical pump bypassed or eliminated.
 
A lien fuel mixture can cause overheating so make verifications for no engine vacuum leaks.

I have been blocking the exhausted passages into the intake manifold especially with blended fuels. Olsons gaskets offers such improved gasket
(blocked) design for the 331.

I always opt for A modern fixed blade flex fan vs electric fan. Adding a shroud is Also not too invasive.

Traffic patterns and usage have greatly changed since the 1950's that engineers could not have anticipated.

[Chopper1942]

The carb spacer, blocking the exhaust crossover passages in the intake manifold, etc. will help fuel vaporization in the carb, but will not help with the engine overheating. Since you have had the radiator rebuilt and system flushed, does the engine overheat/temp increase while driving down the road? If not, the issue is not enough air flow through the radiator when sitting still or a slow speeds when forced air flow is low. The first thing to do is seal the radiator sides to the radiator support with some foam tape. Then seal the hood to the radiator support. This will cause all the air to come through the radiator. Another option is to install a fan with more blades (for example: 4 blades to 5 or 6 blades) and with a steeper pitch. It will pull more air. If you don't have a fan shroud and it still tends to overheat at low speeds, I would install a fan shroud.

Personally, I would stay away from flex fans. I have seen too many flex fan blades stuck through a hood or radiator.

[oldnick]

I would recommend an electric fuel
Pump especially if your area mandates blended (Ethanol) fuels. I prefer to run the electric with mechanical pump bypassed or eliminated.
 
A lien fuel mixture can cause overheating so make verifications for no engine vacuum leaks.

Thank you for your advice (there is indeed a minimum of a few % of ethanol even in the premium grade fuel here), I'll also try to see if some vacuum leaks could mess the operation by checking with a starter spray - though the engine runs fine when cold or the car moving (original radiator and water pump so something maybe to gain there, but I now live far from the supply of proper parts so I'll try that last).

I've read that an electric fuel pump would help and I've updated european cars successufully that way, but I would rather keep the mechanical pump so a last resort mod if I can, plus I'm not sure what type of electrical pump would be compatible with that, to turn it on only on demand without restricting the suction for normal operation - and I made a nice new single piece fuel line taking the original for pattern, I would hate to have to cut it to insert the electrical pump inline - then I don't know if I could manage to hide an immerged pump and somehow plug it to the outlet...

[Chopper1942]

The best place to put a low pressure fuel pump would be near the fuel tank where the fuel line connects to the tank.  This will pressurize the fuel up to the fuel pump and help keep the fuel from vaporizing in the fuel line.

[Caddy Wizard]

I would recommend an electric fuel
Pump especially if your area mandates blended (Ethanol) fuels. I prefer to run the electric with mechanical pump bypassed or eliminated.
 
A lien fuel mixture can cause overheating so make verifications for no engine vacuum leaks.

I have been blocking the exhausted passages into the intake manifold especially with blended fuels. Olsons gaskets offers such improved gasket
(blocked) design for the 331.

I always opt for A modern fixed blade flex fan vs electric fan. Adding a shroud is Also not too invasive.

Traffic patterns and usage have greatly changed since the 1950's that engineers could not have anticipated.

The stock (factory) fan is better than a "flex fan".  The typical flex fan has a blade made in two parts:  a rigid pard and a flexible tip.  The flexible tip uses less power to turn, but doesn't move as much air as a result.  The stock (rigid) fan is far superior in terms of cooling the engine.  The limo models came with a 5-bladed fan.  If you can find one of those, that is a nice improvement over the 4-bladed fan.  Another option is a universal 6-bladed rigid fan (if you can find one that fits the water pump).