The Stovebolt Site Forums The Shop Area Engine Shop fan shroud ?

Can't seem to get a straight answer from all the other sources I've talked to.
I have a 55 series II with a 235ci I6. It doesn't have a fan shroud and I am wondering if a shroud was standard equipment on these models.
Catalogs I have looked at list a V8 shroud but nothing for my truck. Am a bit skeptical of catalogs anyway so I thought I'd ask the experts. Bought a fan blade out of said catalog and it's 3 inches smaller in diameter than my OE fan. Not sure it will work correctly so I haven't installed it yet.
Appreciate any help or suggestions.
Thanks

What size truck?

A fan shroud with a 235 on 1/2-1 ton trucks (at least) was not standard equipment.

A fan shroud was standard equipment on 1955-2nd:
- 4000 series Trademaster (265 V8)
- 5000-6000 series Taskmaster (265 V8)

A fan shroud also came with RPO 256, heavy duty radiator on 3600, 3800, 4000 series

Smaller diameter is much lower air flow CFM.
Example: going down from a 19" to a 16" reduces flow by 29%.

nevermind what I typed; I can't delete this post

Tim answered your question.

Brad

I have the same inability, Brad
I cannot delete a message.

There is a recent blip, I also have been unable to delete posts.

Well, the bright side is that everyone's stupidity will be honored and enshrined in The StoveBolt Archives forever! It is why I rarely post. It's a really worrisome revolting development...

There is no 235 fan shroud that is not aftermarket that I know of. If safety dictates in your mind that it's a necessity, put the V8 model one in. It's as close to OEM as you can get. If functionality is what you are more after, there is no need on the 235 for a shroud.

Have fun whatever you do!

You are, of course, referring to 235 Task Force trucks' radiators not having a factory fan shroud?

What about with RPO 256 (as I posted above)?

The quotes work again! Personally, I think they are overused.

I thought he was referring to a pickup. Which you said yourself they didn't come stock with them. It would be nice and we all know this, if the OP would state clearly the model and particulars. When they do not, we are left with guessing and stating what we know.

He stated he had a 55 Series II, which means a 55 second series truck. A V8 shroud will not work with a 235 due to the location of the fan (close to the radiator). The V8 shroud for anything below 40 Series was meant for desert driving or high temp climate areas. There was a shroud for a 235 in a Viking truck, I had one. It was probably 1/10 the thickness of the V8 shroud. I had a photo of it, but since I sold it a few years ago, I deleted the photo.

Sepp.....put your orig fan on, the smaller one won't be enough to cool the engine. Your 55 2nd series truck doesn't need the shroud to keep the engine cool.

Sepp, I live in the desert where the temp can break 120 and had to be very careful about cooling when I added A/C to my '57 with a 235. I never had any issues with the OE fan until I added A/C.

Here are some my learnings that touch on some of your questions:

-I was not able to find a shroud that would fit. As stated above, the V8 shroud will not fit and I was not able to figure out a way to effectively adapt it. For a shroud to work properly, the tips of the fan blade must be about 1/2 exposed outside of the shroud with the other half inside, so the shroud would have to be very skinny to fit and work properly with a 235.

-Replaced the OE 4 blade fan with a 6 blade one of the same diameter. I was not able to find the optional GM version of this fan that was available for the TF trucks, so I used a repopped one. Send me a PM if you want the vendor info.

-Made sure that the radiator and the block were well flushed. I had some sludge blocking the drain outlet on the rear of the block under the #6 cylinder.

-Changed out the thermostat from a standard 180 degree to a 160 degree.

-I also added two electric pusher fans inside the grill tied to the A/C circuit, but this does not address your questions.

Matt

My 55.2 3100 235 engine didn't come with a shroud. Running a stock fan blade and radiator, and I haven't had any over heating problems.

Maybellene and 55 SHAKER,
Many thanks for your info- I have located a six blade fan here in Germany. It is a universal fit but I'm going to wait until the weather warms up and I can put a few more miles on my truck before deciding. Don't have an over heating problem that I know of. Two weeks ago we had a stretch of mild weather and I drove it every day. No problem at all. Only when I let it idle for 10 minutes or more. Then the radiator overflows. I think that's due to temperature expansion as opposed to over heating. Had the radiator professionaly cleaned and tested. It's like new. Also have a new waterpump and thermostat (180°).
Thanks Again,
Sam

gotta make sure bubbles are gone.. I drove my 52 with the 235 ever where, never had a problem with it heating up.. good luck with your new ride... I sure miss my little red truck

Once you're going 35 mph or more, air passes through the core fast enough that a fan isn't needed at all. Yes, take it off for that trip to California and get better mileage (just remember to take it with you).
At idle without a shroud the fan is just pulling in air from behind and below the radiator and pushing it under the car.
From walking speed to 35 the shroud allows only air that has passed through the core to reach the fan.

Then, why don't they come with one?
1. "none" is as cheap as it can be
2. adding 2" to the fan diameter may fix the problem (but requires more power)