BRINGING IT ALL TOGETHER.... A's, G's & E's


Fan shroud / motor heating on highway

Share
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Fan shroud / motor heating on highway

Post by marco_chevy on Sat Dec 01, 2018 5:05 am

Hi. I read some post and i think my heating problem is the result of having no fan shroud .

I have à 69 v8 307. When bought it , it have a strang shroud fan whit à fan on thé water pump. I remove all that and installed a 18’’ électric fan . Work fine everywhere except on highway at 60-70 mph after 15-20 min , temp go To 195-200 when outside temps is about 28-30 deg. When its about 20 , it run cooler. Thermostat is new 180 . If after highway , i need To go slowly and hide a something ( need more power ) , temp can go To 205-210 whit the electric fan on .

Il chek 2-3 différent timing and change nothing.

I re installed thé water pump fan , and little bit better , but run at 195 on highway after 20-30 min at 70 mph .

So its possible that only thé fan shroud would Yelp ? It Will force the air To Pass trough the rad ?

Where i can get thé right shroud fan ?
avatar
samsvan

Number of posts : 564
Location : Sarasota, Fl.
Age : 55
Registration date : 2014-09-04

Re: Fan shroud / motor heating on highway

Post by samsvan on Sat Dec 01, 2018 5:59 am

http://vintage-vans.forumotion.com/t33555p25-keeping-a-v-8-conversion-cool

I found this thread while dealing with my own cooling issues. A lot of great information. From my own experience, the quality of your electric fan makes a difference and a fan shroud would too.
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Sat Dec 01, 2018 6:59 am

I Chek the cfm of my electric fan ( proform 67016 whit control 69599 )  its only a 2100 cfm , but now i have electric and water pump fan and problèm still the same.   Its why i think the shroud can be the solution !

My electric fan 16’ is in middle of rad , so it not cover all area !   Both fan pull air from rad and push it on the motor .

The shrould would Protec Also me against the fan Smile.  Rad was recored 3-4 years ago by last owner

Or i change rad and fan for a kit

avatar
Skulptorchaz

Number of posts : 277
Location : So. East Indiana
Registration date : 2015-05-08

Re: Fan shroud / motor heating on highway

Post by Skulptorchaz on Tue Dec 04, 2018 7:21 am

I swapped over from a 194 in-line to a 292 in-line and also had heating issues. The one thing that helped the most was a belly pan I fabbed. It helps the most at highway speeds.
But, as far as electric fans, I run two. I could cover more of the radiator. I put them at the inlet and outlet of the radiator, and definitely on the engine side.
I put one on the ignition switch and one on a thermostat, hard wired to the battery so it runs after the engine is turns off to get the heat out of the dog house (as well as gas fumes).
YMMV.
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Tue Dec 04, 2018 7:41 am

I have the direct fan and electric fan whit thermostat , connected to swich but i let key on 1-2 min alter turn off motor. It help for heat and vapor. Start better after 5-10 min Smile

I have the original belly pan but maybe it is mot very powerfull.
avatar
Digz

Number of posts : 3771
Location : United States Six Lakes MI
Registration date : 2008-05-17

Re: Fan shroud / motor heating on highway

Post by Digz on Wed Dec 05, 2018 4:27 am

Not knowing what you have for a radiator I would suggest getting that checked out for any possible plugging from corrosion. Going slow the electric fan by itself really should keep it cool enough. Speeds above 45mph it should run cool enough with its own airflow pretty much. Is it a down flow radiator or a cross flow?
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Wed Dec 05, 2018 5:50 am

Downflow or cross flow ?   I dont know. It was rebuilt 4-5 years ago buy the last owner, i have an invoice or 260$ for that.  I think its like original !

When going slow, no problem. Idle, no problem.  Only when go about 2500-3000 rpm more than 15-20 min , i can see temp go to 190-195 and thermostat is 180 .  Its like no wind pass trough radiator

When outside amp is under 25 , all is ok . I see that trouble when it’s 28 and more whit big sun .
avatar
Digz

Number of posts : 3771
Location : United States Six Lakes MI
Registration date : 2008-05-17

Re: Fan shroud / motor heating on highway

Post by Digz on Fri Dec 07, 2018 5:17 am

Think I will go along with needing the right fan shroud like you say. 190-195 isn't bad as long as it doesn't get much higher than that. My proform fans seems to have a lifespan of 4 years . Need to change mine out before spring. I'm on my 3rd one .
avatar
Skulptorchaz

Number of posts : 277
Location : So. East Indiana
Registration date : 2015-05-08

Re: Fan shroud / motor heating on highway

Post by Skulptorchaz on Fri Dec 07, 2018 6:28 am

Just to be sure, the electric fan is on the "motor side" of the radiator, correct? I kind of assume it is but not sure I read it. That is important.
Why I ask is because altho I am running a big six, I could not fit a big fan in the center of the radiator. It hit the pump. I don't know how they fit on an eight. So I used two smaller fans and they cover more radiator to boot.
Anyway, just checkin. Hope ya get it figured out.
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Fri Dec 07, 2018 9:00 am

Yes. Fan is motor side. Its about 1/2’’ of the water pump pully
avatar
donivan65
Governor
Governor

Number of posts : 11676
Location : San Diego, California
Registration date : 2008-05-12

Re: Fan shroud / motor heating on highway

Post by donivan65 on Fri Dec 07, 2018 10:14 pm

Do you have the stock, 4 row of tubes, crossflow radiator with the surge tank, fan clutch, and shroud?     Maybe get a heat gun and shoot the radiator to see if there are clogged up tubes,,,,,,also get the radiator sniff tested to see if there are head or head gasket problems,,,,,



avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Sat Dec 08, 2018 5:11 am

I have the cilinder tink on the top of rad like pucture .its really look like the pic! I dont have the fan clutch , and dont have the shroud. What you mean by 4 row of tube ? I think head or gasket are good because level is always ok , color is ok too, no overflow, no smell !

I was thinking that was a timing problem .

So I run at idle 2 btdc ( like I see in manual ), total timing ( vac on ) at 2500 of 36 , at 3000 , 38
I run idle 4 btdc , total timing at 2500 of 38
I run idle 6 btdc, total timing at 2500 of 40-41

And I can’t see difference on heating. Look the same . But start easier whit hier timing when hot .

I see some post talking of 10-12 idle timing , it will give about 46-48 total timing , it’s really high!

avatar
donivan65
Governor
Governor

Number of posts : 11676
Location : San Diego, California
Registration date : 2008-05-12

Re: Fan shroud / motor heating on highway

Post by donivan65 on Sat Dec 08, 2018 3:18 pm

tubes connect the side tanks together,,,,the more rows, the thicker the radiator is,,,,and more tubes mean more cooling fins to cool down the coolant as it goes from the hot thermostat to the cool water pump,,,,,,,another thing,,,,that surge tank holds the radiators coolant,,,,its not an overflow tank,,,,,proper level of coolant is 1 inch below the cap,,,,,
avatar
marco_chevy

Number of posts : 110
Location : quebec
Registration date : 2015-05-23

Re: Fan shroud / motor heating on highway

Post by marco_chevy on Sat Dec 08, 2018 4:38 pm

1 inch under the cap of the surge tank , when cold ?

Originally , it’s a 2 row radiator ?
avatar
sandyvan

Number of posts : 485
Location : San Diego, CA
Registration date : 2011-03-13

Re: Fan shroud / motor heating on highway

Post by sandyvan Yesterday at 3:55 pm

Water jackets in block plugged up? Can't a person flush the block after removing freeze plugs? Just guessing...

I have a very recently rebuilt 307 in my 69 G20 108. factory fan shroud, fan on water pump but no fan clutch. When I had the stock radiator out for the engine swap I flushed it good with a garden hose till it ran clear. it does not leak (I got lucky on that). I run at 185-195.

Sponsored content

Re: Fan shroud / motor heating on highway

Post by Sponsored content


    Current date/time is Wed Dec 12, 2018 12:33 am