347 RUNNING HOT

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
23,672
8,754
203
Two things come to mind, coolant flow above idle and timing,
What is your timing set at?
Is the lower hose collapsing when you rev it up?
Was the radiator/fan-shroud installed at the same time, like a set, or replaced the radiator then added the fan-shroud after?
 

Zeffer

Member
May 27, 2020
43
19
18
Do you have an aftermarket trans cooler?
Yes, enters rad first and then to a B&M cooler in front of a/c condenser.
Is the air dam in place?
All factory air dams are in place and in good condition.
I don't recall,how did you "burp" the system? I never had a problem with any of my Foxes,except my current one. I HAD to use a no-spill funnel to get the air out. BTW,I'm running a 331 with turbo. Champion radiator,HD water pump,HD fan clutch.
I had the front of the car jacked up as high as I could get it, filled with 50/50 mix, ran engine with rad cap off until thermostat opened, adjusted level and closed cap. This is the way I have always filled cooling systems.

I am a commercial transport tech and have drained and refilled hundreds and hundreds of cooling systems in my 30+ year career and have never had any air lock issues like what have been described here. I've worked on everything from 302's to Cat, Cummins, Mercedes and Detroit diesel engines as well as a lot of 460's in class A motorhomes. I worked at a Ford dealership for 21 years in the "truck" shop, so I've never worked on the car side of the vehicle line only trucks, and there were a lot of 302's in trucks back in 1989!

This is why I am so stumped, everything that's been suggested to me has proven to be fine, with the exception of the few who think it's my fan/shroud combo.
Like I stated a few times previously, the car acted the EXACT same with my stock fan and shroud in place.

Thank you all for taking the time to reply
 

Zeffer

Member
May 27, 2020
43
19
18
The car does not have a fancy road racing nose on it right?
Cutting off some air flow to the radiator?
The car is 100% stock appearing, I have collector plates on it.
Two things come to mind, coolant flow above idle and timing,
What is your timing set at?
Is the lower hose collapsing when you rev it up?
Was the radiator/fan-shroud installed at the same time, like a set, or replaced the radiator then added the fan-shroud after?
Timing is set at 10 deg and was confirmed with the Holley as per their instructions. This should be a good base for timing, I plan on getting it tuned further when I can cure this overheating issue.
I have never checked the lower hose while reving it up, it is a new hose (without spring) though.
Rad and fan/shroud combo were installed at the same time.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
23,672
8,754
203
Rad and fan/shroud combo were installed at the same time.
Ok, timing is not the issue, I suspect a flow issue, water pump has an issue pushing coolant through the engine or pulling it from the radiator, check the lower hose for collapsing when rev'd up, there is a possibility the water pump impeller is defective or slipping on the shaft, take the back of the water pump off and inspect.
Now let's talk about the continued critic of the fan\shroud setup.
While I have no personal experience with the sve radiator \fan combo I know several applications where it works just fine but the fan\shroud part has numerous complaints,, every one that I have read about say their car runs hotter at speed, the air apparently cannot flow through the radiator adequately because the air cannot escape through the fan openings so it 'packs' in front of the radiator and stops the flow through it, the fans can pull the air good enough at idle or low rpm situations, don't know how better to explain it, that design was originally for drag racing applications, it may work ok for your driving conditions :shrug:
I believe you have a coolant flow issue although another possibility would be excessive heat from a high stall converter transferred to the radiator through the trans fluid that was why I suggested just using the outside trans cooler.
 

Mstng93SSP

You have a nice rear end there Dave.
15 Year Member
Nov 29, 1999
2,844
3,467
184
If this is the fan setup you have, https://www.americanmuscle.com/mishimoto-dualfan-7993.html#customer_reviews go look at the 1 star reviews and read them. "does not keep my car cool" "

"Don't buy.....
Over all, nice look and fit. They just don't get the job done. The cfm's are not enough. My car constantly runs hot....."

"
Star_1.png
11990 Mustang - RZ
Installation Time: Less than 1 Hour

Not enough CFM

Ordered this for my fox gt40 heads, cobra intake 130 alt nothing to much daily driver. Set up looks good but could not keep up, ran hot smh not wroth it check cfm rating before buying.

ETC. ETC!!!
 
  • Like
Reactions: 1 user

KRUISR

5 Year Member
Apr 16, 2015
1,364
608
133
I'm late to the party but will through my 2 cents at it.

Recap as I read it and my thoughts:
- Your car runs 190 deg at idle no problems or concerns - I assume this is temp taken from Holley X. If so, this would be engine temp, not coolant temp. What is temp at discharge side of rad? I also assume at idle the fans do turn on.

- Trans cooling line goes to rad and then aux trans cooler - I agree with others, skip the rad unless you need cold weather warming of trans fluid.

- Lower rad hose with no spring - my Fox does not have the spring either, it would be needed if you have collapse. I would get the car up to temp at idle, then rev it up (2000-3000 rpm and hold) and observe the lower hose to see if it collapses. That should answer if you need a spring inside.

- Timing at 10 deg is fine

- Coolant burping - I have always burped the same way and never had an issue.

- You have had this cooling issue with both stock rad/fan shroud and aftermarket fan/shroud and therefore do not believe it is the problem - this seems logical but consider this, if your stock fan clutch was failing and that was the reason for the issue at first, you may still have a shroud flow issue now. Here is why I think this way. My current setup is a 3 core OEM brass style rad with Contour fans and a 180 deg T-stat. If I drive at highway speed on a 70 deg day my temp gauge will read around 180 the whole time. Your system running up to 220 on the highway on a similar day makes me think you are not getting proper air flow through the rad/shroud/condensor/aux cooler. My fans (low speed set for 205, high speed at 215) will NEVER come on when moving on a 70 deg day. On a hot day, my temp will hover around 195-205 (my estimate on the factory gauge) because my fans still don't come on when moving at highway speed (they will come on in traffic and slower speeds)

My fan controller temp sender is in my lower rad hose, not on the engine. Why. Because you want your fans to cool the coolant in the rad, not cool the engine, and really the only place to measure coolant temp leaving the rad (after the rad has done its job) is on driver side tank or lower rad hose. If your Holley is only getting a signal from the sender in the heater core tube, you are getting engine temp, not coolant temp going into your engine. In my opinion, this is not where you should be controlling fans from.

Here is a thread I did on installing Contour fans, but the stand alone control can be applied to any dual fan set up, even to run PWM fans in a non PWM two speed mode.


To test the air flow through the shroud issue, remove the shroud, rehang the fans (even temporarily for a quick jaunt down the highway to test) and go for a drive on the highway. You indicated above that temps on a 70 deg day got up to 220. What happens during this test? The fans are there for back up to get home, but the real test is will temps stay around or under 200 on the highway without the shroud restriction. This will point to shroud or not and really only costs some time.

Good luck and keep us in the loop.
 
  • Useful
Reactions: 1 user

TOOLOW91

If you're the village idiot what's that make me?
15 Year Member
Nov 29, 1999
7,964
7,994
234
Time out- verifying the 10 degrees of timing is vastly different on a Holley then a stock ecu . I have been running a Holley since 2017 before a fox kit actually existed .

All you’re doing is syncing your dist mechanically to the Holley so that what you input into the timing table is actually what you see mechanically . The check is so that if you have to move the dist , crank trigger - whichever to make sure you’re synced you do it . Once you clear the static timing check - NOW your timing table is accurate and what the engine is seeing . So your timing table untuned could also play a major role in over heating as well as If the tune is lean .

Also ditch the fans . Or drill holes in the shrouds and put some rubber flaps on the shroud like the higher end fans have so you get air flow through it On the highway or while driving. At some point the electric fans sort of become a restriction at speed because they are pulling air through but eventually the air speed coming in has to over come the amount the fan blade and move and not exactly make it through the opening for the fans .

Only time I ever had an issue like this was when it bought a engine the t stat was in backward and I had no idea. It would run hot on highway and cool idling and on street .

I have a Big bore 347 - centri blower , FB AOD , pretty decent stall and drive my car 60-70 miles minimum when I take it out . Even in summer it’s never been past 210 ish In dead stop traffic and it cools down once you get moving again.
 
Last edited:
  • Like
Reactions: 1 user

Zeffer

Member
May 27, 2020
43
19
18
Well guys (girls).....

I have an update for everyone.

I confirmed both of my head gaskets were orientated correctly. I replaced my thermostat with a Stant 160 degree with a bleed hole in it and made sure it was installed with the bleed hole facing up. I removed my Mishimoto fan/shroud combo and refilled the cooling system with straight water only (just for the interim) and bled/burped it like I always do. I took the car out today, 24 deg C = 75 deg F, I found a road I could drive on with no traffic and the car never climbed above 185 degrees while cruising.:)
I owe a lot of you apologies that were insisting it was the fan combo....:(
I did a little more research and found a rule of thumb is a small block requires 2600-3000 cfm, when you have an engine a little more on the performance side you may need more....Contour fan setup is in the future now!
I see on Summit they have the Dorman #620-104 equivalent listed, has anyone used that? LMR is out of stock on theirs.

THANK YOU ALL FOR YOUR INPUT!!!
 
  • Like
Reactions: 1 users

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
39,455
15,302
224
New Contour fans are so cheap, there is no reason to buy a used one.

Kurt

The OEM fans pull a few more CFM than the aftermarket ones. The motors are a bit more powerful. However with OEM ones being 20 years old by now, not sure I’d use an old crusty fan on a nice new build.


My Dorman unit however is plenty adequate and even on a warm day I really only need to run it at 70% of full speed to keep my car cool without the ac on.


Oh and I would bet the LMR unit is just your typical parts store fan or even a dorman unit anyway.
 
  • Useful
  • Like
Reactions: 1 users

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
23,672
8,754
203
The OEM fans pull a few more CFM than the aftermarket ones. The motors are a bit more powerful. However with OEM ones being 20 years old by now, not sure I’d use an old crusty fan on a nice new build.


My Dorman unit however is plenty adequate and even on a warm day I really only need to run it at 70% of full speed to keep my car cool without the ac on.


Oh and I would bet the LMR unit is just your typical parts store fan or even a dorman unit anyway.
Mostly my point about shopping LMR for common replacement parts, nothing against them, they have great customer service (my experience) but replacement parts are found cheaper from parts stores.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
39,455
15,302
224
I know, and I feel bad reiterating that point. LMR has been good to me the times I’ve needed their great customer service. In fact, their customer service is the best of any company I’ve ever dealt with anywhere.
 
  • Agree
Reactions: 1 users

revhead347

Apparently my ex-husband made that mistake.
15 Year Member
Jun 14, 2004
9,107
1,653
214
Oh and I would bet the LMR unit is just your typical parts store fan or even a dorman unit anyway.
Having several years of parts experience, and once being ASE parts specialist certified, I assure you it's an aftermarket knock off. But at the end of the day, Dorman is a pretty good company. Much better than A1 Cardone anyway.

Kurt
 
  • Agree
  • Like
Reactions: 1 users

rednotch

Founding Member
Aug 14, 2000
456
191
63
I would suggest the made in Taiwan four season 75282f or the after market ones. Has a better blade retention system them most... Not uncommon for those to strip on the repo's using the square spring clip..
 

Zeffer

Member
May 27, 2020
43
19
18
My saga has come to an end....
I ended up installing the Dorman copy of the Contour fan setup, set fans to come on at 185 deg in the Holley, road tested today and temp never got above 192 deg, did more driving today than I have all year!:)
Thank you all for your input....looking forward to getting some Holley tuning done now.
 
  • Like
Reactions: 4 users