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Discussion Starter #41
Thank you sir for the follow up I try to help when i can.
This is cool, the bottom part is what I had in mind. I am not exactly sure what I am seeing on the top part. My radiator has a large gap and it looks like you blocked off the path for air to hit the condenser and roll up and over the radiator by sealing it off. The photo does not give me the full picture, but I think that is what you did (and it makes sense).

I had an ideal to tape it off with aluminium tape for a hack trial, but a little tin-work would be a better way to go and probably mixing adhesives with hot metal....

Based on you pre and post test, do you feel this aero helped cooling substantially?
 

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Based on you pre and post test, do you feel this aero helped cooling substantially?[/QUOTE]

Sorry it I don't think k it helped much at all What fixed my issue was replacing the fuel pump and strainer.
Good luck.
 

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Discussion Starter #43
Based on you pre and post test, do you feel this aero helped cooling substantially?
Sorry it I don't think k it helped much at all What fixed my issue was replacing the fuel pump and strainer.
Good luck.[/QUOTE]

Based on my impression of success with the louvers, I think I will give this a shot when the temps get into the 70's and see if it helps. My overheat was primarily on the high-speed side of things, so aero is still on the table for me. The louvers looked like they knocked out about 7 deg F for me in that condition. Keep in mind that is 225 to 218F... before and after. I'd like to keep under 220 even at 90F ambient, so I'll need all the help I can get. I am starting to believe I will need a new radiator to ensure I don't have a problem on the efficiency side. Wizard cooling has been very informative (thanks Jim....) and I think I'd tap them for a radiator if I go that direction.

In other news, Spal has a new brushless fan that blew me away. (I don't care if you laugh at my jokes...)

This fan is not impressive from a CFM standpoint, but it is slim and has tons of volume at high static pressure. Guys.... if you are reading this thread because you care about e-fan of S/C cooling be 100% sure you know the difference between advertized flow and static pressure flow before pulling the trigger on a product.

I can't tell my static pressure at 50 mph, but I am sure it is up there....

I may try this fan out or I may get lazy and have Wizard sell me a radiator/fan combo unit and only wonder which one makes the difference.... Worth chick out if you need an e-fan. Be sure you are looking at brushless and the website does not help, I had to google the catalog and look it up myself.
 
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Time to break out the flow-vis. Do your fenders have vents behind the front wheels? It is hard for me to call it aerodynamics wirh a Jeep, even though it is. Maybe airflow management?

Not relevant to this project, but interesting. Sauber wind tunnel tour.

https://youtu.be/KC0E0wU6inU
 

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When I was experimenting with my cooling system I had a Ford Crown Vic electric fan which provided adequate cooling at low speeds, but not great. A 4x4 shop in Montrose, CO (Rockwerx) fabbed a shroud from aluminum which dramatically improved its performance except at highway speeds. They cut vents for added air flow at high speeds (I think there were flaps to close off the vents at slower speeds). I got tired of the money and time invested in diddling with the cooling system so I returned to completely OEM (with new radiator and flushed the system) and problems solved - even with a boosted engine.
 

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Discussion Starter #47
5/23/19 UPDATE

As was the case with so many who came before me.... Cooling issues are often a mechanical issue in disguise...

I finally broke down and decided to replace the head gasket after finding only minor returns on the other efforts. It began as an exhaust manifold leak suspected, and then I thought I might as well do both and cross that off the list.

Then the fun began...

After re-install I did a leak-down test. All were in the 2% range except cylinder #5. 97% leakdown. A bore scope and several rated -R rants later, the pistons were pulled to discover that #5 was cracked (but not into small bits) and the block was A-OK.

I think this issue was not the cause, but rather the victim of the cooling issue I had. I suspect the head gasket was failed, but would only hurt badly when in boost (also found at highway speed). The intake/Exhaust manifold began doing the same thing where it was fine at NA, but hissing at boost.

Now.... I decided not to stroke, but rather deck the head and the block, bore .030 over, switch to DSS forged pistons and replace the scat rods. Cam showed a chew from the original OPDA issue and so both the CS and the now chewed "new" OPDA will be replaced as well.

Yes, it's a super big bill (unless you have some talented friends, then it's just a big bill..) I post all this not so we can judge if $1700 in motor work is justified, not to judge the supercharger setup and challenges and not to get into the merits of strokers but to publish the chain of events on the forum for those of you who find similar evidence of problems. I wonder if I had just done the head gasket last summer if this setup would have lasted 150K miles... we will never know.

As an aside, hyper eutectic aluminum pistons in an iron block are awesome, but not recommended for boosted applications. The compression and the thermal concentrations and impulse forces that may result from the boost warrant the forged pistons. These forged pistons are actually not as tight of a tolerance particularly the Coeff. of thermal expansion, but if you have an 04-06 you may have bad cast lot pistons that often spit the skirt. These stock pistons are fine for N/A and are highly engineered, but for the stock environment. This does not mean you can't blow the engine without a piston upgrade, but I would recommend considering this upgrade. As you read, I had 5 perfect pistons, and one shot one, so no argument that this forged piston upgrade is a must, but it is looking like a smart move especially for someone in my position now.

Why bore 0.030" over? well I decked the head and block. I intend to dish the pistons about 17cc (about stock) to conserve the volume and slightly lower my compression. This will allow me to run with the tune that I do not want to go through all over again. I am happy with the power and TQ band so my desire was to re build my former setup with high reliability over the opportunity for more advancements in power. This also allows for another more over to .060 if I ever needed to, which I hope is in 40 years.

Yes, you can stroke and bore your way to 50-80 more horses, but I don't want more heat or complications. I will replace the cam shaft with it'sand the eaten up gear and I will replace the OPDA with a Crown aftermarket (with proper oiling) re-assemble, break in and I hope my "overheat" will go away by virtue of well setup gaskets and no air in the system at any boost level.

I am grateful to everyone who posted support and appreciation for airing what now looks like a fool's chore, but I feel like these mistakes can serve as a good cautionary tale to others. I cannot wait for the final result and I will be sure to update in a month or so when I can tell if this was a total success or the start of a new chapter of troubleshoot...

More to come. Jeep season is here and I while I drove all year, haven't hit a trail since October!
 

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Good job digging into it and finding the broken piston before there was cylinder damage. That rebuild bill may be unexpected but sounds reasonable given what you're doing. The peace of mind when it's done is well worth the investment. I can't wait to hear how it runs when the project is complete.
 

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Discussion Starter #50
Update 6-20-19

Engine went back in. Broke it in with the builder. Ran hot (220F) even with no hood and a massive shop fan during break in. After about 2 hours of break in, we did a short test drive and noticed some exhaust leak type noises.

#4 cylinder was not holding compression, yanked the head to inspect the valve.... looks good. Yanked the motor again, looks like a score on the cylinder wall that was not present during the build. Honing is going on now, reseat rings and try again. Not a good feeling but I got some good guys on the case with a local engine shop.

Not 100% sure what will be the diagnosis here.

On the overheat, I am certain the last elements are fuel pressure and tune. I don't want to send it back to Virginia, but I think once all is back together I can datalog my way to a new tune. I am working with Stinger to ensure I don't have a fuel pump issue. I will check fuel pressure once I have an engine again.

Glowing headers at 2200rpm for 15 minutes seems like exhaust temps of a volcano are going on. Live data shows advance bounces around from 10-180 degrees and are all over the place. Some of that could be due to the bad compression on cylinder 4, but I will need a new baseline.
 

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We've had great success running a mostly stock cooling system with our Currie built / Kenne Bell supercharged '03 Rubicon 4.0, auto transmission, 35" BFG AT's, 4.88 gears, and Currie 4" suspension + 1" body lift. Cooling system has worked great, both rock crawling and on the highway for 14 years / 27,000 miles since the Kenne Bell SC installed.

The only cooling system upgrades we did were:

•*Flow Kooler water pump
•*Turbo City high flow thermostat
•*Mopar 7 blade fan (upgrade from stock 5 blade fan)
•*AEV Heat Reduction Hood

Exhaust system upgrades were:

•*Banks Torque Tube exhaust header
•*Borla catback exhaust

My 2¢ worth suggests installing a stock radiator, shroud, and Mopar mechanical fan (7-blade if you can find one). I upgraded the cooling AND exhaust when we installed the Kenne Bell SC since I knew it would produce more heat... and haven't had cooling issues.
 
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