Heat riser question 51 232

[lelshaddai]

I have been working on the heat riser for the 51 232. Had advice to try and get it unstuck before looking at a new one. I worked on it and it does move freely now. The question I have is whether it is working properly. When it is cold the weight is horizontal/parallel to the ground and weight part is towards the front. I would assume that is open position. When the car warms up the weighted end drops down but not to a 90 degree angle but about 60degrees. I assume that it is supposed to close but is not completely. Should it drop to a 90degree angle? If not can you loosen the spring one turn so it can move to that position?

[Alan]

In Arizona, I would toss it and put in a spacer that is sold by Stude vendors.

[StudeRich]

This has been explained in YOUR String on Post #2 here:

http://forum.studebakerdriversclub.com/showthread.php?109991-Which-Pertronix-for-51-232-12v&p=1148039#post1148039

I believe you are understanding it Backwords, it is normally Closed when UP and OPEN when Forward and down after heating, that is IF it is installed with the "UP" marking facing Up!

[lelshaddai]

Just to make sure I’m assuming it needs to be a solid spacer?

Still wanting to know if my riser is working like it should. Just for my own reference.

[lelshaddai]

That is not how mine works. It looks like a bar with a round weight on the end and it is already horizontal. When it heats up it is falling down. But it does not fall all the way straight down. I know this is the correct heat riser because at the show this weekend a 52 had the same one.

[DieselJim]

I don't use heat risers here. I also block off the passage under the carburetor. Put a electric choke cover on. I also store the car in the winter. To answer your question, a spacer is used so the exhaust will clear the cross member.

[gordr]

The heat riser valve should be close when cold, and open when hot. If it hasn't been messed with, the bob weight acts to open the valve as the bimetal spring heats up and loses some of its tension. There is nothing sinister about heat riser valves. Practically every auto maker has put them on most of their engines for the last 70-odd years, because they improve cold weather driveability and reduce cylinder wear caused by raw fuel washing oil off the cylinder walls. If the heat riser valve is stuck closed, the car should perform well when cold, but might be prone to preignition, and run-on when shut off. If the heat riser is stuck open, the engine will be slow to warm up, and will be prone to lean stall, or intake manifold backfires when cold.

Do you have access to a laser infrared thermometer? I see one for $17.99 in the flyer of a certain nationally-known tool dealer. Take readings on the left and right side downpipes as the engine warms up, and the action, or lack thereoff, of the heat riser valve should be evident in a few minutes.

[lelshaddai]

Thank, that was the information I was looking for. I have a laser thermo. I will look at that.

[lelshaddai]

Tested the temp on downpipes. Passenger side was cooler than driver side. Though the heat riser is not stuck it only moved under acceleration. I could push it down with a screw driver but the spring pulled it back up. When I pushed it down the downpipe temp reduced by almost 50degrees. Is the spring too strong?

[gordr]

If the heat riser is open, both downpipes should be at about the same temperature. They may not be exactly the same because of different fuel distribution between sides, or vacuum leaks, or simply more cooling fan breeze on one side or the other. But if the pipe becomes cooler when you press down on the weight, that tells me the heat riser valve is open, and you are closing it by pushing down on the weight. I would say it is working correctly. With the heat riser valve closed, most of the right bank exhaust is forced through the crossover passage in the intake manifold, in order to warm the carb up, and operate the automatic choke. Note that the heat riser valve is nowhere near a perfect seal when closed; there is about an eight of an inch clearance between the butterfly and the casting, all round. Also, at anything over a fast idle, the engine makes enough exhaust pressure to force the heat riser valve open against the bimetal spring.

[altair]

I have two heat risers one works as per normal with the weight upward when cold and near horizontal when hot. The second unit is totally backwards, at rest when cold it is open. These units can be assembled backwards, I took one of these apart and it took me at least three tries to get it back together correctly, the springs can go in backwards. Both of these units fit the Studebaker manifold however one is correct and one is not. Therefore straight up is cold and closed and horizontal is open. There are some variables, some models may be closed horizontal and open pointing downward. Either way the weight offers assistance to open the butterfly and the spring tension will overcome the weight when cool

[StudeRich]

Number 6, 7 and 8 are NOT Stude. and Wrong, I have no idea What that one is.

The New ones available now are reproduction Cadillac, and have a Half Round counterweight instead of the hat Shaped Studebaker one.

[StudeRich]

Number 6, 7 and 8 are NOT Stude. and Wrong, I have no idea What that one is.

The New ones available now are reproduction Cadillac, and have a Half Round counterweight instead of the hat Shaped Studebaker one.

The other thing is; the 232 like the OP has is a smaller unit due to the smaller Manifold and Headpipe than the 259/289 1955 and on Heatriser.

[lelshaddai]

6,7,8 is what I have. The friend of mine with the 52 has the same one. If you look at pg 1 (picture of the V8) of the 51-54 Chassis parts book that is the exact unit I have. My weight starts at about that position and falls down. I think I have it working somewhat. It does not fall down 90 degrees but much better than it was.

[altair]

# 6, 7, and 8 may be wrong and not Studebaker, however I purchased it from a vendor at the National meet and he assured me it was for a Studebaker. The unit fits perfect however it is backwards and is open when cold at rest. The spring may need to be reconfigured so that it is closed when cold. The springs are very easy to put on backwards. Any heat riser will do the job if configured correctly.