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Discussion Starter · #1 ·
My 88' Esprit has aged up enough so that the ABS fan shroud has crapped out...

There seems to be options all over the board from fabing my own to getting rid of the thing all together. Now, the design of the original suggest that each fan is able to pull air with limited interference from the other fans... hence the shroud. The idea I think is that this gives some efficiency.

However, given the aluminum radiators available today, I find myself questioning the need...

To that point, anyone have any thoughts on replacing my OEM radiators and fans with these offered by Wizard Cooling? This radiator seems quite good and would have to be better than my OEM... although my car does not run hot even in the Alabama summer heat unless I am just sitting for a while. then it cools down once the fans kick in...

Wizard Cooling Custom Radiators. 1988-2004 LOTUS Esprit Custom Aluminum Radiator

Low profile fans are clearly able to move more air given the number of blades... and bolt (not zippy tie) to the radiator.
 

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I have seen the Wizzard radiator for the Esprit, but be very careful when selecting anybody's radiator. Radiator technology has made many advances in the last several years. Vendors are reluctant to provide thermal data, mainly because they don't have the information, as they buy out someone else's cores. Aluminum radiators must be isolated from the chassis as their oven welds will not tolerate any flexing, so you need to modify the way it is mounted. Row count is no longer a gauge of the radiators cooling ability, louvered fins and wider row spacing are more thermally efficient. Shrouds should be made with a plenum area (.75" minimum) to allow air re-distribution if a fan fails. Ram air flaps reduce the possibility of reverse air flow at low speeds with the fans running.
 

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Wingless Wonder
1988 Esprit Turbo
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I've had my radiator out twice. The first time, I reinforced the cracked OE shrouds with thicker fiberglass, and the second time (three years later) all was good, no further damage.

FWIW, I'm still using the OE brass and copper two-row design (re-cored in 2009), and the OE Ford fans.
 

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Discussion Starter · #5 ·
Good stuff in the shared thread/Thanks for the info!

My fan shrouds are the real issue. Totally apart.There will be no layovers or fixing with this one. Not by me anyway.

As I understand it, this is a part that was originally made from unobtanium, although it resembled ABS.


So, I am looking for the best solution. clearly, replacing with the aluminum radiator is not it! With it all out, I might can fab up a shroud out of aluminum? Wood? LOL!

Anyway, thanks a lot for the info. I'll prob keep my OEM radiator... as this seems to be the best option. You'd think that the shroud is a part that creates enough problems for someone to have picked up a replacement manufactured? There certainly seems to be a number of cars that no longer have them or owner that have had to fix or fab one up...

Cameron
 

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Good stuff in the shared thread/Thanks for the info!

My fan shrouds are the real issue. Totally apart.There will be no layovers or fixing with this one. Not by me anyway.

As I understand it, this is a part that was originally made from unobtanium, although it resembled ABS.


So, I am looking for the best solution. clearly, replacing with the aluminum radiator is not it! With it all out, I might can fab up a shroud out of aluminum? Wood? LOL!

Anyway, thanks a lot for the info. I'll prob keep my OEM radiator... as this seems to be the best option. You'd think that the shroud is a part that creates enough problems for someone to have picked up a replacement manufactured? There certainly seems to be a number of cars that no longer have them or owner that have had to fix or fab one up...

Cameron
I recently repaired my radiator fan shroud with ABS plastic strips and ABS cement. Worked well!

Cracks




Repairs





I also rethought the foam seals at the top and bottom of the radiator that act as the air dam to make sure the air goes through the rad, rahter than around it. The foam was holding water and corroding the radiator! SO I made my own 2" rubber bulb seals out of a rolled up rubber mat riveted together and smashed above and below the rad. Seems to seal really well, and shouldn't hold the water as much.

This


Replaces the rotten grey foam you see here
 

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[snip]
So, I am looking for the best solution. clearly, replacing with the aluminum radiator is not it!
[snip]I'll prob keep my OEM radiator... as this seems to be the best option.

You'd think that the shroud is a part that creates enough problems for someone to have picked up a replacement manufactured? [snip]
I forgot to update that radiator thread: the vendor replaced the radiator with a new unit (but I did have to pay labor to have it R&R).

If the replacement cracks again in 20 months, I have the original radiator/fan assembly (rodded out and cleaned) on standby.

RE: shroud: I can't find it, but there is a thread here where someone shows photos of how he created his own shroud to use Spal fans he sourced individually. This was mounted on the original OEM-type radiator (?).

He created his own molds, etc and it was pretty nice, but alot more work than I would tackle.
 

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Wingless Wonder
1988 Esprit Turbo
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RE: shroud: I can't find it, but there is a thread here where someone shows photos of how he created his own shroud to use Spal fans he sourced individually. This was mounted on the original OEM-type radiator (?).

He created his own molds, etc and it was pretty nice, but alot more work than I would tackle.
It was Tony Grasso who fabricated his own shroud, but apparently the photos never made it to his How To pages. :sad:

index

PS, regards repair of a cracked shroud: My repair included drilling small holes on either side of the cracks, and actually STITCHING the ABS together with stainless cable, then fiber-glassing over the stitching. Unfortunately I didn't take any pics of that operation.
 

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It was Tony Grasso who fabricated his own shroud, but apparently the photos never made it to his How To pages. :sad:

index
Hmm...I couldn't find the shroud stuff on his index (?).

Here's another option - I know you said your shroud needed work, but if felt the need for upgraded fans (FYI there are debates whether 'upgraded' fans are truly necessary) - here's a post on using Spal fans on the OEM shroud. I'm thinking of this if I convert back to OEM brass radiator:

http://www.lotustalk.com/forums/f164/aftermarket-g-car-cooling-fans-162385/#post2335273
 

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Wingless Wonder
1988 Esprit Turbo
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Hmm...I couldn't find the shroud stuff on his index (?).
It's not, Tony did that work AFTER he moved to AZ, along with his Headliner and Carpet Repair...




I can see it in my memory but the pages have gone down....maybe a search in the Internet Archives AKA "WaybackMachine" would find them:

https://archive.org/web/

It would have been 2004 - 2006...
 

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I don't know about Tony G. but Jim Knowles fabricated a shroud using fiberglass. It came out pretty nice but he swears he'd not do it again.

If you are repairing your original shroud I would not recommend fiberglass it really doesn't bond well to ABS plastic. as Travis noted there are specific ABS repair materials that would be the preferred thing to do with the shroud.

I have also thought about (but never done) how you could make a shroud from sheet aluminum. Another thought is that if you are pretty good with fiberglass you could use your old shroud as a mold model, make a plug, and produce a new fiberglass shroud. If one of the Lotus brethren out there who is really talented in the fiberglass fabrication realm made a useful mold, perhaps it is something which could be lent/.rented/sold to others to fabricate their own shrouds. The original ABS shroud is nothing to be proud of, especially longevity-wise.

When I rebuilt my '89 I had bought Tony Grasso's old shroud and fans and mated it to my radiator which had been re-cored. Tony's shroud was in good shape - I just had to repair a few minor cracks. I still have the three spare OEM fans in my parts box. I have my original shroud which I kept because I had this idea of using it as a model for a mold to produce a really nice fiberglass shroud that incorporated Spal fans. So I have done a fair amount of reading and youtube watching on fiberglassing, but I have not gotten off my lazy butt to put this idea into action!
 

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Wingless Wonder
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If you are repairing your original shroud I would not recommend fiberglass it really doesn't bond well to ABS plastic.
Again, I wish I had taken pictures, but I didn't.

To further elaborate, I STITCHED the FG matting across the cracked ABS on each side, then applied resin to BOTH sides.

Probably overkill? Sorry, that's Just the Way I Am.

+++++++++

Four years later I pulled the rad again, and everything was holding up fine AFAICT. :up:
 

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GRRRRR!!! After participating in this thread, I decided to check my expansion tank (it was 16 oz LOW after about 1500 mile drive since Dec 27).

Brought the car to the mechanic - the replacement aluminum radiator is LEAKING again after only 7 months (!). Car now has 58K miles (28K/27 months on my watch).

Now the twist - the mechanic is suspecting a blown head gasket (pressurizing the coolant system with exhaust pressure. causing the leaks seen at the hose/pipe fitting).

I had a Blackstone analysis about 6 months ago - no coolant in oil (but high lead/copper PPM). But clearly the loss of coolant (no apparent drips except now on the radiator). He thinks it's possible to have head gasket leak that pressurizes the cooling system (?). It's sounds incredible to me - high pressure in the cooling system should blow a cap or hose, not crack aluminum? The first radiator definitely had cracks.

He will get test kit tomorrow to determine if exhaust gas in coolant.

Curious to see the outcome; maybe my first radiator leaked due to the same reason? :-(
 

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Wingless Wonder
1988 Esprit Turbo
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Wouldn't the coolant pressure cap vent excess pressure? It should be 15 pounds rating. So, a HG leak would have symptoms other than coolant leakage at the radiator.

Just a note here: After my first rad removal, I didn't get the top hose fully seated on its inlet. Coolant started leaking there three years later. That is why I pulled the rad a second time.

Lesson learned: Connect the big hoses BEFORE installing the radiator back into the car.
This requires knowing the orientation of the hoses...take pictures.
 

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Atwell is correct, the pressure relief cap should vent excess pressure above 15psi. If it's working correctly...

On the other hand the coolant loss could be due to a pressure cap that can't hold 15psi, and you may be loosing coolant out the expansion tank behind the rear wheel while driving...?
The cap was tested (for a different reason) about 3 month ago - it passed the 15PSI test, but we didn't specifically for EXCESS pressure. Mechanic will be checking for that today as well.
 

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[snip]
Just a note here: After my first rad removal, I didn't get the top hose fully seated on its inlet. Coolant started leaking there three years later. That is why I pulled the rad a second time.

Lesson learned: Connect the big hoses BEFORE installing the radiator back into the car.[snip]
With the first radiator leak 27 month ago, I took pictures of the radiator after removal - it clearly was leaking from minute cracks in the aluminum; the hoses appeared to be correctly seated.
 

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Now I'm glad I had my radiator recently re-cored... with copper!
The part that's killing me - the mechanic says the Elise/Exige all use aluminum aftermarket radiators *similar* to mine - without incident.

But what's not clear is if the MOUNTING method (rubber isolated - not possible with stock Esprit fiberglass tray) has something to do with it.

And since I'm one of the few running an aluminum radiator AND 1K miles/month of daily driving - I think my scenario is unknown territory for durability.

I'm going over to the shop right now to check out the status (lunchtime and only 3 miles from my work) :evil:

Just got back - test kit was ordered late in day so arriving tomorrow. The Elise uses similar radiator from same vendor without incident, so concentrating on eliminating head gasket-related cause.

If it turns out to be another radiator failure, that'll be a big disappointment.

You can rejoin this older sub-thread back here - apologies to the OP:

http://www.lotustalk.com/forums/f164/aftermarket-aluminum-esprit-radiator-leaking-after-20-months-150618/index4.html#post2780985
 
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