Club Cobra - Overheating Issues, Perplexed

Page 9 of 13

Show 20 post(s) from this thread on one page

Club Cobra (http://www.clubcobra.com/forums/)

- ALL COBRA TALK (http://www.clubcobra.com/forums/all-cobra-talk/)

- - Overheating Issues, Perplexed (http://www.clubcobra.com/forums/all-cobra-talk/97316-overheating-issues-perplexed.html)

jwd	06-15-2009 01:02 PM

Quote:

Originally Posted by elmariachi (Post 958316)

No way its the engine.

Then my question would be "Why did Brad not have the problem you are having and the only thing changed was the motor (to a smaller one with less HP)?" Just doesn't make sense.

Jim

elmariachi

06-15-2009 01:15 PM

Quote:

Originally Posted by jwd (Post 958328)

Then my question would be "Why did Brad not have the problem you are having and the only thing changed was the motor (to a smaller one with less HP)?" Just doesn't make sense.

Jim

Fair question and I agree, which is why I posted this thread. Maybe his aluminum engine and heads were just within the capabilities of this fan and radiator, coupled with a much less harsh environment in Michigan versus Texas. In other words, maybe the cast iron engine and heads, coupled with the temps here, are a tad too much for the cooling system.

I am not arguing against there being something wrong with the engine, but I have far more data supporting an airflow/cooling system capacity issue than I do an internal engine issue. The engine was properly tested, machined and rebuilt and it performed flawlessly on the dyno. There are no combustion gases in the coolant, no coolant in the oil, I was present when the head gaskets were mounted, so on and so forth. It warms up normally. Oil pressure and temps are good and no matter how hard I run it, it stays cool. I ran the piss out of it yesterday afternoon and it was 95*F here with 50% humidity. It never got over 85*C while moving.

Wayne Maybury

06-15-2009 01:28 PM

Quote:

Originally Posted by elmariachi (Post 958316)

When I got it home and bolted it into the go-kart, I then put 20+ miles on it running around the subdivision before mounting the body and it never got above 180*F. Then I mounted the body and it started idling hot. No way its the engine.
.

I have been following this thread from the beginning and I am amazed at how thorough and diligent you have been at trying to solve this problem. I know that this is a crazy idea and involves a lot of work but if you cannot find the problem to your 100% satisfaction, why don't you remove the body and see what happens? I also think the problem may be the engine, not the cooling system. By taking the body off, you can see if it still runs hot once and for all.

Wayne

elmariachi

06-15-2009 01:42 PM

Quote:

Originally Posted by Wayne Maybury (Post 958335)

I also think the problem may be the engine, not the cooling system. By taking the body off, you can see if it still runs hot once and for all.Wayne

The car is presently painted Lamborghini Titanium with silver stripes. All along it has been my plan to repaint it to a more original color. That's been a "Fall 2009" event and my preference would be to not pull the body until then. I have a bigger fan and shroud coming and even if all we are doing is masking the problem, I may live with it until the fall so that I only have to remove the body one more time. But let's go down this path for the sake of discussion...

If I pull the body and it still overheats, then what is wrong? What about the engine >>specifically<< could be causing this?

CobraEd

06-15-2009 01:47 PM

Retarded timing and/or lean mixture at idle.

.

elmariachi

06-15-2009 02:11 PM

Quote:

Originally Posted by CobraEd (Post 958340)

Retarded timing and/or lean mixture at idle.
.

We've already been there some pages back (not expecting everyone to read every post in this massive thread.) Offline to this thread I have worked on timing and mixture with CC member "Patrick." We started out at the dyno settings of 20* base + 18* advance (which is where it was before mounting the body.) We then went to 18+18 and we are presently at 16* initial + 21* advance for a total of 37*, all in my 3200 rpm. It does seem to idle bit cooler now than it did at 20+18. Certainly idling cleaner and not so gassy.

I also have Don Gould's Word doc entitled "4 Seconds Flat" and he advises 24* initial + 10* advance via his 10* MSD bushing, which I have lying here on my desk but haven't tried. His whole argument around FE timing is not in line with what is recommended by people on this forum, but I am trying to approach this one step at a time.

After lots of road testing and using a vacuum gauge I am 1.75 turns out on the primary and 2 turns out on the secondary, Mighty Demon 750 Annular. Plugs look great and it runs and transitions great. Car starts time after time, no strain/knocking/pinging or backfires.

Jerry Clayton

06-15-2009 05:25 PM

does your demon carb have the idle eze adjustment feature in the center of the base plate? the mixture screws on just about all demon carbs that i have done anything with usually end up around 1 1/4 turns out---

you seem to be quite attached to the theory that it ran ok on the dyno and before the body was on the car----so what----forget that nd work on what you have now--runs hot---no dyno involved

To borrow some words from one i've never met---if the facts don't support your theory, get a new theory( Al Nunley)

elmariachi

06-15-2009 05:36 PM

Quote:

Originally Posted by Jerry Clayton (Post 958401)

And where would you suggest the Idle-Eze be set?

Quote:

Originally Posted by Jerry Clayton (Post 958401)

you seem to be quite attached to the theory that it ran ok on the dyno and before the body was on the car----so what----forget that nd work on what you have now--runs hot---no dyno involved
To borrow some words from one i've never met---if the facts don't support your theory, get a new theory( Al Nunley)

I am not attached to it as a theory, its the facts. Do you have a recommendation?

jwd	06-15-2009 05:57 PM

I will add one thing about your timing. Now I'll admit I've never even owned a FE motor However, I've built and tuned many SBF, 460's,SBC and BBC some putting out over 600 HP and from where I stand, those timing specs. listed above are way out of line. What I shoot for is around 10 initial with a total of 36-iron heads and 34 for alloy heads all in by 2800RPM. You absolutely MUST have a dist. with vacuum advance that adds 8 dist.(16 crank) degrees and have it hooked up to a constant vacuum source. That will give you a total of 26 at an idle yet still be easy to start. The advantage of this set-up is better throttle response, better gas mileage AND a cooler running engine at all RPM's. I've never seen a motor that didn't run better with vacuum advance.
Jim

elmariachi

06-15-2009 06:14 PM

Quote:

Originally Posted by jwd (Post 958411)

You absolutely MUST have a dist. with vacuum advance that adds 8 dist.(16 crank) degrees and have it hooked up to a constant vacuum source. That will give you a total of 26 at an idle yet still be easy to start.

I'd like to hear other thoughts on this from the FE crowd. Anyone running this setup?

ERA Chas

06-15-2009 07:01 PM

Quote:

Originally Posted by jwd (Post 958411)

The advantage of this set-up is better throttle response, better gas mileage AND a cooler running engine at all RPM's. I've never seen a motor that didn't run better with vacuum advance.
Jim

And what do you do when your idle vacuum is 7" with a 250+ cam?

Jerry Clayton

06-15-2009 07:05 PM

If you have the idle eze---do you???
The throttle blades should be set so as to only have a small portion of the transfer slot showing, sort of like a square hole showing vs a slot. and then set idle speed with the idle eze valve

jwd	06-15-2009 07:11 PM

Quote:

Originally Posted by ERA Chas (Post 958429)

And what do you do when your idle vacuum is 7" with a 250+ cam?

Well, if you have a MSD dizzy, you can use a GM vacuum advance unit (that's all MSD uses) part.# vc 1807, 1808, 1809 or 1812 depending on how you want to fine tune your timing curve. All of them start at 5" of vacuum and are all in by 7".
Vacuum advance is one of the most mis-understood parts of an engine and my guess is that 99% of those out there have no idea how to properly tune an engine for the best performance.

Jim

elmariachi

06-15-2009 08:11 PM

Quote:

Originally Posted by Jerry Clayton (Post 958431)

I have experimented quite a bit with the Idle Eze. With both transfer slots at .020 like a square, the car would not idle at 16, 18 or 20* initial no matter how far out I went with the Idle Eze. So I set the Idle Eze at the default setting of 1.5 turns out and went in on the primary idle screw about 1/2 turn. It now idles fairly smooth at 1000 rpm.

I also tried running it with the Idle Eze closed (Don Gould and a couple others offline said that I didn't have enough cam to benefit from it and to close it) but the problem then was an unstable idle.

Jerry Clayton

06-15-2009 08:59 PM

I think the idle eze is a very good thing altho of course they aren't on some carbs and none of the holleys---for years I have been putting a 1/4 npt plug in the center hole of the base plate and drilling a small hole in it for idle air that I get to the center with a small cross milled groove on the top side of the base plate--it usually takes from an .085 up to .125 depending on engine and cam size--i have been able to get a steady idle at around 850rpm on most engines and that is low enough that the mech advance hasn't kicked in and the engine will shut off without dieseling---most times also the idle mixture screws will be at 1 1/4 turns to as little as 7/8--never had to go past 1 1/2

We also take the feed wire for the fan directly to the alternator like you except we do use a relay to turn the fan on and off---

I noticed going back and reading all this thread that initially with the pic of your radiator that you said it was a 3 core(post 12) and later a 2 core (post 68). Is it a 1 inch tube or a 1 1/4 tube and how many fins per inch???

Glad to hear your making progress

elmariachi

06-15-2009 09:26 PM

Quote:

Originally Posted by Jerry Clayton (Post 958460)

--i have been able to get a steady idle at around 850rpm on most engines and that is low enough that the mech advance hasn't kicked in and the engine will shut off without dieseling---most times also the idle mixture screws will be at 1 1/4 turns to as little as 7/8--never had to go past 1 1/2

Jerry, would the fact that I am at sea level in Houston have any effect on mixture? I can run it at 1 to 1 and 1/4 turns out on the primaries, but it likes 1.5-2 a lot better and the plugs look better as well.

Quote:

Originally Posted by Jerry Clayton (Post 958460)

We also take the feed wire for the fan directly to the alternator like you except we do use a relay to turn the fan on and off-

I noticed going back and reading all this thread that initially with the pic of your radiator that you said it was a 3 core(post 12) and later a 2 core (post 68). Is it a 1 inch tube or a 1 1/4 tube and how many fins per inch???

Yes, I am using a relay as well, tied to a 180* thermo electric switch.

I just corrected that post #12, that should have been 2-row, thanks for catching that. The PRC I have is a 2-row radiator with 1" rows. As for fins-per-inch, there are 16 individual fins, or 8 "V"s in one inch. How does that compare?

Thanks for the help and advice.

xlr8or

06-16-2009 12:42 AM

Question for elmariachi... Are you doing this testing with the hood on the car and closed? Is there a rubber seal around the hood opening? If yes on the hood installed it's an easy test to try it out without the hood. Underhood temps could be contributing to your problem.

elmariachi

06-16-2009 08:43 AM

Quote:

Originally Posted by xlr8or (Post 958510)

All testing is being done with the hood up in the driveway. I have a rubber seal between the hood and body. For what its worth, once I managed to get the car to idle at 195F using the second pusher fan in the nose, I observed the following IR temp readings with my new gun:

- Intake manifold surface by the temp bung 180-185F
- Valve covers on header side 165F
- Carb body 135F
- Expansion tank surface 200F

This is in the hot sun with oil temp level at 215-220F.

undy	06-19-2009 07:29 PM

Quote:

Originally Posted by elmariachi (Post 958282)

Same for me, I am going to get the fan and make sure all systems are go before I worry about wiring.

The more I read, the more confused I am getting. The SHO fan is supposedly a 16" swept blade with two speeds and was produced in early to mid 90's. According to an email I received from the Seller, the fan I bought is actually a 17" blade with two speeds from a later model Lincoln Continental/MKVIII. But the pic I have looks just like the SHO fan. He also says that there is another Lincoln fan out there that has 18" chopper blades and requires 6" mounting depth, but it blows a whopping 5500 cfm.

So I am not sure about all these fan models, I am just regurgitating what I am learing through reading. No wonder American auto makers are in the toilet, too many discreet part requirements when one or two fans could have served the model whole lineup for a decade.

Here is a link with some good pics and part #s for Ford/Mercury and Lincoln:

http://www.monsterautoparts.com/MERC...ing_fans-1.htm

El, .... got my fan today via Epay. It looks just like your posted picture. It's a sweet setup and for 80 bucks brand new what a deal. I'm getting ready to do a 12 volt hookup to check operation and flow. It looks like it can be adapted for my application.

What type of control center are you going to use for yours?

Dave

elmariachi

06-19-2009 09:15 PM

Quote:

Originally Posted by undy (Post 959691)

El, .... got my fan today via Epay. It looks just like your posted picture. It's a sweet setup and for 80 bucks brand new what a deal. I'm getting ready to do a 12 volt hookup to check operation and flow. It looks like it can be adapted for my application. What type of control center are you going to use for yours?Dave

Hi Dave. Still waiting on mine but that's okay, its hotter than hell here in Houston and my energy level is looowwww. I haven't really thought out the wiring, though I do think I am going to buy that Hollister relay wiring kit I mentioned earlier. I think I'll hook it up so that the low speed comes on with the 180 elec temp sensor in my radiator hose, and the high speed is dash switchable. So down the road it will either be off because the engine is running cool enough or on low speed, but hi speed is reserved for low speed driving and idling.

All times are GMT -7. The time now is 10:33 PM.

Page 9 of 13

Show 20 post(s) from this thread on one page

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: