View Full Version : Radiator and fan for 6.2/6.5 swap?
03-16-2012, 11:21 PM
I'm still in the planning and prep phase of my project to put a 6.2L in my 78 Wag. I was wondering what you've done for cooling in your 6.2/6.5L swaps.
I was planning on getting one of BJ's aluminum radiators for Chevy swap. It seems like this is the most efficient radiator available for a FSJ with Chevy hoses. Their 2-speed fan and shroud seems OK, but 2400 CFM seems a bit light. The belt-driven fan has close to 10,000 CFM and the best electric Flex-a-Lite single fan pulls 3,200 CFM.
And what'd you do for oil and tranny coolers? Any aux fans under your hood?
So what radiator did you go with? How much room did you have for a fan? Which fan are you using? Any and all details welcome!
03-18-2012, 09:07 AM
I waited for someone with 6.2/6.5 experience to answer you. I'm doing a Cummins swap. A lot of people have done Cummins swaps with the newer, more efficient, radiators of OEM size and haven't had problem. Cummins can make huge amounts of heat.
My feeling, not experience, is that a newer generation, more efficient, radiator/fan combo of OEM size would handle your needs. Things to ensure would be to make sure all the air hitting the front of your truck is actually going through the radiator by sealing all the cracks and gaps around the grill work and to use a fan shroud so it pulls all its air from through the radiator.
PS- If you haven't called them, call BJ's. They are knowledge about your questions.
03-18-2012, 11:53 AM
I like Resbum's advice. Seal it up well. Consider adding louvers for airflow (although there are a thousand differing opinions on that subject). If there's room you can stick with a Jeep clutch fan. I re-used my 258's fan and shroud, worked just fine.
I have a 2-row crossflow aluminum radiator for my 6.5 turbo, and it's barely sufficient. I'm going to do something like he did, widening the radiator area and getting a new bigger rad. Sell you my current one, cheap! :) It might work well for a stock 6.2.
I have plate-type coolers, one for oil under the driver floorboard and one for trans under the passenger floorboard. Not the best location, but I've never had oil or trans temperature issues.
Good luck, and keep us in the loop!
03-20-2012, 10:36 PM
Thanks for the feedback guys. Resbum, I started reading through your build thread and wanted to say thanks for the detailed writeup and pics. I think I'll go the route you went by widening the radiator supports to fit in a wider radiator. The Flex-a-Lite 58000 looks like a nice choice.
Still wondering how those electric fans will compare to the stock belt-driven one. But I really want to ditch that stock fan and go electric.
Budojeepr, what was the clearance like between pulleys and radiator (V-belt or serp)? And is your engine set forward or back in reference to your original bellhousing?
03-22-2012, 03:24 PM
I bought a Hummer fan for my '82 Silverado 1t 6.2...works GREAT!
03-22-2012, 03:44 PM
GM diesels run hotter than a Cummins. The indirect injection is the most likely culprit for that. They even have cooling problems in a factory installation, and the radiator is huge compared to a stock FSJ. Get as big a radiator in as you can, and try to install it at an angle to the ground, no straight up and down. Mounting them at an angle forces the air to impinge on the cooling fins, increasing the efficiency of the radiator. Something Jeep did right...
03-22-2012, 09:23 PM
Thanks Trenchfoot, glad my thread could help.
Thanks JeepinPete, I never knew the GM's run hotter than the Cummins.
I am running a Banks Turbocharged somewhat built 6.2 and used a Griffin Aluminum racing radiator. I bought it from Summitt if I recal correctly. I bought one that was cross flow and just fit in the core support, but is four rows thick for a big-block hi-performance engine. Thus far, I have not had a cooling issue, but I ahve not run it over the hot summer months with A/C running yet either. My fingers are crossed.
I thought seriously about widening the core support for the rad but it (the suppoort) is part of the mounts to the frame from my recolection, and apeared to require some more advanced mods than I was willing to do at the time. Hopefuly, this was not a mistake. I'll post pictured once I figure out how to do so. I have literally hundreds of the whol process, from engine mounts, to linkage to masaging the inner fender wells to get it all to fit.
I installed a honda intercoller inside the grill in front of the A/C condensor, and then two 12" square plate style cooolers underneath it, one for oil, the other for trans. I have a spot for the p/s fluid cooler, but have not installed it yet. Again, if I can figure out how to load photos, it would help explain it better. Let me know if you have any questions, or want me to send you photos directly.
03-23-2012, 07:32 AM
Trenchfoot, I moved the radiator forward about an inch to clear the fan. This time 'round I'm trying to avoid that.
Neo, use Photobucket or other photo service to host your pics. The post editor on this site has an icon for you to click that will allow you to paste in the address of your hosted pic so the pic will show up here.
There are lots of threads here dealing with pic posting.
And I NEED pics of your intercooler installation. :thumbsup:
03-23-2012, 08:19 AM
GM diesels run hotter than a Cummins.
Cummins (at least the 12V) run very cool. I didn't put a fan on my rig until June of last year. I pulled our 9k travel trailer for 2 hours and went over a couple of nice hills and it never got over 200 degrees, this was in 60 degree weather.
03-23-2012, 10:05 AM
:thumbsup: You guys just keep making me feel better about not overheating when I have to haul heavy.
03-23-2012, 02:34 PM
Thanks for the feedback guys. JeepinPete: I'd never have thought of angling the radiator to increase heat transfer.
Neo: get those pics uploaded and linked! Sounds like you've got some good info to share.
We've got about 37" between the fenders. Subtract the width of the rad supports and you've got about 35" for radiator if you move the supports. Resbum's build (http://www.ifsja.org/forums/vb/showthread.php?t=151930&page=2), post #39+40, has great pics.
I wanted to let all you owners of older 6.2Ls know that Peninsular Diesel has finally gotten their high output water pumps recreated. It's a standard rotation pump for V-belts and flows ~110 GPM (stock is ~80). I called today and the first one is getting tested this week and the first batch might be available in a week or two. At ~$140 they aint cheap. But considering the heat the 6.2 generates and the limited internal space and frontal area in a Wag I'm going all out to keep it cool.
Arg! I just posted a reply and accidentally closed it!:banghead: THat is frustrating.
ANyways, I used the Pennisular pump as well. Bought mine several years back when they were in stock. Also, used a standard fan/clutch. Can't recall exactly which one i used. It is very tight - probably 3/4 to 1" best between the radiator. I believe it is probably sufficient, proivided the clutch does not give way. Here is a link to the photos in my photo bucket: http://i1048.photobucket.com/albums/s376/rosbrughjb/EngineINPlace.jpg
There are more there, and I will be adding several hundred more when I remember to bring the memory stick with the images home. Will take me a while to catalog them, then I'll to a build thread.
Currently have it torn apart again to redo the wiring. Was never really satisfied with the initial install. Have a couple other things to do also: 1. Air intake - like to do snorkle. 2. A/C lines and compressor mount for the Sanden 709 and 3. Fan shroud. I plan on buying a fan shroud.
Feel free to contact me with any questions in the mean time, if I can help, I will.
03-26-2012, 11:38 PM
Good info Neo, thanks for info. That's what I was looking for. Can't wait for the build thread.
03-27-2012, 06:34 PM
Did you check out the Humvee fan? Mine works GREAT in my 1ton
03-27-2012, 06:59 PM
Did you check out the Humvee fan? Mine works GREAT in my 1tonI missed your first post. The fan (http://www.hummerpartsguy.com/FAN-COOLING_p_3712.html) is something to think about. Here's another source:
Good info Neo, thanks for info. That's what I was looking for. Can't wait for the build thread.
Here is a link to the "fabrication" folder. Have not had time to label/name the photos to explain what they all are yet. Will do so as soon as I can find some time. Been working on wiring fixes.
Hopefully, this will work. Once I get the pics labeled, I will do the build write-up.:D
The PIG Smith
04-27-2012, 04:29 PM
I'm doing a Cummins swap. A lot of people have done Cummins swaps with the newer, more efficient, radiators of OEM size and haven't had problem. Cummins can make huge amounts of heat.
I think you will be surprised at how cool a Cummins can run.
My brother has a 1997 Ford F-150 that came from the factory with a 4.6L V8.
This truck is now powered by a Cummins 4BT that sports an inline P style injector pump.
With the OE Ford radiator, his 4BT runs too cold.
In the winter, he sticks card board in the front of the radiator to try to get the coolant enough to produce some heat.
I've not been told of anyone building a special uber radiator to cool a Cummings 4BT or 6BT in a FSJ.
Any of the larger radiators currently offered for sale by any of the FSJ vendors would serve you well.
05-01-2012, 04:42 PM
I've been calling Peninsular for months now about their 109 GPM water pump for V-belt 6.2L engines (p/n 6253316). They finally have them for sale. They quoted a price around $200 which was a surprise, I pointed out they had them online for $143 (this product has sold out) and they honored it.
Either way that's a lotta coin for a water pump. But I'm not taking any chances with my 6.2L.
vBulletin v3.5.4, Copyright ©2000-2013, Jelsoft Enterprises Ltd.