My overheating, radiator solution

Thought I'd share the solution I used for my 350 overheating issue.  My van was running at 230 degrees in the matter of a few minutes.  Pretty extreme heat issue.  I recently replaced the water pump with a Milodon high flow pump.   Replaced the radiator with an aluminum one from Howe, part number 342A2816NF.  I also used an aluminum Howe surge tank, part number 3424.  I am using a 180 thermostat, with dual electric fans, pushing and pulling.  My van is now running at a steady 190 degrees, in 90 degree weather. Hope this can help anyone still searching for a cure. I'll try to post some pics.

I've been thinking about getting that same radiator for my 68. How did you mount the bottom of the radiator? Do you have any pics of that?

I like your surge tank. Where did you get that?

I'm using stock style bottom mounts, with the rubbber insert that it sits in. Top mount is just sheet metal bent around top with flat rubber under it. The surge tank is a Howe tank, I ordered through JEGS.

How many rows is the radiator? thanks

It's a two row.

My van cooled off 15 degrees by just putting on the belly pan. a MUST.

Thanks for the post!

Hey Vanquished,
I went ahead and bought your setup but I have a questions; What did you use on the side with the AN fitting?  I was thinking of using a AN coupler to an 1.25" fitting.  Something like this
1.25" fitting

Well, I was not alone in my NEW heat issue it seems! Glad to have company in the heat!
I bought and I am having the Milodon High Flow water pump and High flow thermostat installed this week.
I have a new 4 core radiator and expansion tank already. I had not driven much while getting the van going. Now that I am driving it more, I see the heat gauge going to 230-240 within 12 miles of travel.
I  had to take it back to the radiator guy to make sure the radiator was fine (brand new only 100 miles)? It was... now it must need a new water pump, I think the old original one is still on the engine.
It will be great to not be sweating bullet's with the box cooking next to my leg! I actually got a burn and blister it was so darn hot!
With summer fast approaching I gotten get this fixed!

Is overhearing a common issue when you upgrade to a 350? Just swapped out the 305 in my 67 with a 350. Freshly rebuilt corvette water pump installed as well. My van still has the fan shroud and belly pan as well.

I know this is an older thread but I just bought this radiator setup for my 69 with a 350. It works great but today on my 200 mile maiden voyage in about 90 degree weather doing 70 on the highway for a while the temp was climbing up to around 210. My question for anyone is does the Milodon high flow water pump help that much and what is the belly pan supposed to look like? I’m ok at metal fab work and planned to build one just based on common sense but it would be nice to see one. I also installed the condenser for the ac system I am installing and am wondering if that is jacking with my air flow (what little there is lol). I’ll post some pics of what I’ve done so far, that is if I’m smart enough to figure out how to do that...

Still breaking in the crate engine, so I’ve been taking it easy on the speed, been at about 145 degrees on the highway cruising at 60-65. Last weekend I started to increase the speed to 65-70 and it’s still just over 145 degrees.  I do have a rebuilt 63 Corvette water pump on it, not sure if that makes a difference. I do believe the belly pan does make a difference in the airflow. I’ve tinkered with the engine then driven off without latching the hood and at a certain speed the cover will try to blow open.

sittingheavy69 wrote:I know this is an older thread but I just bought this radiator setup for my 69 with a 350. It works great but today on my 200 mile maiden voyage in about 90 degree weather doing 70 on the highway for a while the temp was climbing up to around 210. My question for anyone is does the Milodon high flow water pump help that much and what is the belly pan supposed to look like? I’m ok at metal fab work and planned to build one just based on common sense but it would be nice to see one. I also installed the condenser for the ac system I am installing and am wondering if that is jacking with my air flow (what little there is lol). I’ll post some pics of what I’ve done so far, that is if I’m smart enough to figure out how to do that...

SH,
Welcome to VV.  You might try looking at this thread.
Picture posting

Jim

Thanks Jim! Here are a few pics of the radiator and condenser installed.

Oh yeah and a shot of the van!

Hey sitting heavy, Was your fan running when the A/C was on? It should kick on whenever the a/c compressor kicks on.

I've been curious about this one from Jegs: https://www.jegs.com/i/JEGS/555/52008/10002/-1 I love the driveway pic and think I'll save it to look at when I'm bitching to myself about how inadequate my shop is.....

@azdon man the dimensions are right on that one from jegs but (and I’m no expert) I think if you run that one with a cap you need to do something like get a thermostat housing with a cap or rig a surge tank that’s higher to deal with the fact that you cap is lower than the top of the engine. Hot air bubbles steam and what not. I’m sure some dudes on here can explain it better than me lol, but that’s why I got the Howe setup it has no cap and has a spot to put fittings for the surge tank like the stock setup. And yeah it all goes down in the driveway, the shop is for motorcycles lol!

@67vanhelsing the condenser was just the first step, I am still building the compressor mount so the fans are just on switches for now. For my test drive I was just running the puller fan the whole time. I flipped on the aux fan (on the condenser) but it didn’t seem the help. I did another run today and figured out it is definitely an airflow problem because I kept the van running for like 3 hours today driving around and leaving it running everywhere I went and it stays perfectly cool around 190 the whole time in 97degree weather. When I get on the highway around 70mph it will slowly creep up after about 10 min of that speed. If you slow down or get off the highway it cools right down again. My theory is at that speed the air rushing under the van causes sort of a vacuum in that area that my puller fan is pulling from (I think the reason they designed a belly pan). To test this theory I jumped on the highway and took everything out of my pockets and cleared the passenger seat and then opened the doghouse (hung from a bungee cord) then went ripping down the highway. Hot as f*ck in there but I could run 85-90mph for as long as I wanted and she stayed a perfect 180! I drove like that for like 20 min and almost melted into my seat lol! Anyways I went today and picked up a sheet of aluminum and I’m going to start building a badass under scoop belly pan. I’ll post pics when I get it done but I’m pretty confident that will solve it!

Agreed it may be an airflow issue. Good luck with the custom belly pan. Post pics once your're finished!

Take some of that aluminum and build a fan shroud. Might help?

A lot of the high efficiency condensors (including vintage air) out there are too restrictive of the air flow and I know of numerous cases of street rods that began overheating when one of these condensors was installed.....If you look at factory-style A/C condensors, the tube and fin patterns are very loose to allow ample air flow.... I used a Vintage Air Condensor on a 63 pickup I built and didn't have a problem, but I left about a two inch air gap between it and the rad and it was only half the size of the rad....
My inclination would be to not stack radiator-like devices, but to have substantial air gaps and separate fans and deflector/air scoops for each one, so they each get at least some fresh air of their own...
Also, Yes, I do understand that the radiator cap needs to be at the top of the system

Thanks that’s good advice, I mounted the condenser about 1” away but the mounts were easy to make so I probably will try and give it more space if the air dam doesn’t fix it. This one is from southern rods air and I think it’s just like the vintage air one my dad put on his nomad. It does look really restrictive to me.

I made a half assed first version of my belly pan and it actually works well! I plan to improve it but it was cheap and super easy to make and I drove it for 3 hours each way starting in okc with 103 degree temp and it stayed 190-200 for a while then settled at around 200-205. That was running around 85+ on I-40 in the heat. I am good with that temp because as I understand it with my radiator and a proper surge tank (had mine pressure tested before the trip) and a 17lb cap I should be good up to 230 with no problems. Here’s some pics, I know I said I would make a “badass” scoop but I was in a hurry to get something made before the camping trip lol! If I get around to making something better I’ll post pics but I can promise you that just this half assed first version works and made a pretty noticeable difference. When I was driving at night I could turn off the fan and it would not climb too much. Also the doghouse is cooler, I can rest my arm on it and it’s not hot (in the front it was still pretty hot on the back part) I know it makes a difference because before the belly pan the whole doghouse cover was like a stovetop!