Overheating issues on the 73 440

[postman]

No sediment in bucket is good. If when you opened the petcock the water wasnt muddy, thats a good sign.


I would worry about the bubbles. Keep fingers crossed they go away. If not... I have experienced, stretched headbolts, failed head gaskets, cracked valve seats, and cracked heads and blocks only visible with magnaflux (google it.) Is your fluid recovery tank (if so equipped) dirty?


For my $0.02  I would makes sure bubbles are constant before you chase gremlins.

What pound is your rad cap?

[mattyj858]

Thanks, actually the recovery tank is usually dry, my guess is it does hold water, pretty old. I'll check what both my caps are, I have one on the top of the radiator and one off a hose in front of the radiator to add coolant. I just replaced that neck hose. What pound should they be?


I'm going to flush and replace top and bottom hoses and hope for the best! Weird it didn't over heat today? Last weekend the temp rose quickly.

[postman]

I have seen lower hoses seperate plys (if you will) inner part would tear and seperate enough for the water flow to cause it to fold and block flow. Do an autopsy on the old hose. Remember @ 3000 rpms that water is moving!

[M & J]

I did a generic search for 1973 440 radiator cap and 16 lb. cap was the bulk of the returns.

But I'm no expert. But Super Dave is.


If you havent visited his website you should.


http://dave78chieftain.com

[DaveVA78Chieftain]

I did a generic search for 1973 440 radiator cap and 16 lb. cap was the bulk of the returns.

That is just a simple matter of reading the service manual.

The 318 and 413 used in the M300/M375 chassis pre 73 were rated at 7PSI, 185 deg

The 318 and 440-3 used in the M300 (RM300)/M400 (RM350)/ M500 (RM400)/ M600 chassis'  73 & up were rated at 16PSI, 185 deg

Please note that dates are for the chassis, not the RV as Winnebago typically placed this years model (e.g. 1975) on last years Dodge Chassis (e.g. 1974) because they had to order the chassis early.

[Rickf1985]

And the recovery tank should have a line on it with the cold and hot fill levels. It should be filled to the appropriate level and maintained there. This keeps all air out of the engine so you don't have to worry about hot spots. Plus, if you do have a bad head gasket and the bubbles continue then you would see them in the recovery tank. Once you fill the tank it will take a couple trips to get all of the air out of the engine but after that you should never see bubbles coming from the hose into the recovery tank. If you do it is not an automatic diagnosis of a blown head gasket, you could be pulling air in as it cools off through a bad radiator cap or any number of places in the cooling system. A combustion tester would be the next test to see if there are combustion gases in the coolant.

[postman]

Showing my age here.

Raised in Amarillo Tx it was common to use waxed cardboard in the winter (the wax waterproofed) and cut it to fit to block the radiator airflow. With a good temp gauge it was a good diagnostic tool. If you actually had a cooling system problem, the temp would shoot up.

you could calibrate the temp. Big trucks still do it.

just a thought
... and what Rick said

[M & J]

Super Dave strikes again!

[mattyj858]

Thanks guys I'll take a good look at the recovery and seal any cracks.

Thank you for all the info on the radiator cap!

Really appreciate everyone's help.

[postman]

mattyj858

Just wondering if you were able to definitely diagnose your engine overheating problem?

[mattyj858]

mattyj858

Just wondering if you were able to definitely diagnose your engine overheating problem?

Not yet, I put the whole thing on the back burner till after the holidays. I ordered the 180 skirted thermostat. I plan a radiator flush, drain, replace thermostat and upper and lower hose, fingers crossed after that! Checked again and I have good coolant flow so praying the pump is still strong

[postman]

sounds like a plan See ya in 2018

[mattyj858]

 Hey guys, finally getting back around to the cooling issue. I ordered a Mr. gasket #4367 skirted 180° thermostat  and will be installing it later today along with new hoses and a radiator flush. Quick question on the skirted thermostat does that have to be seated in any particular direction? I don't see any indexing or anything that would show me that it has to be dropped in a specific way thanks

[Sasquatch]

No, drop it in.  Just make sure you fully burp the system of air.  Let it run with the radiator cap off for quite a while.  It will work out all the air in the system.

Are you sure your fan clutch is engaging and disengaging properly?  You should be able to hear it clearly when you are driving and it engages to cool the motor.  If it does not lock up when hot, you will never be able to cool the beast.  Fan clutches are a sore subject with mechanics now a days.  It seems that they only last a couple of years.  I change the one on my MB every 3 years or so when they fail.  I went with electric fans on my coach. 

[mattyj858]

No, drop it in.  Just make sure you fully burp the system of air.  Let it run with the radiator cap off for quite a while.  It will work out all the air in the system.

Are you sure your fan clutch is engaging and disengaging properly?  You should be able to hear it clearly when you are driving and it engages to cool the motor.  If it does not lock up when hot, you will never be able to cool the beast.  Fan clutches are a sore subject with mechanics now a days.  It seems that they only last a couple of years.  I change the one on my MB every 3 years or so when they fail.  I went with electric fans on my coach.

Great thank you. I did a quick test on the fan clutch and I know it's engaging, just not sure if it's turning off when it supposed to. That might be step two after I do all this today. Thanks so

[turbinebronze]

Just a heads up on the Mr.Gasket thermostat. I bought the same one and had it fail (stuck closed) on a test run. At the same time I found the factory gauge was not accurate....and I took out a head gasket on my 318-3 from the overheat. When I took it apart I tested the stat in a pan of water with a candy thermometer. The stat never opened in boiling water.
I try to check thermostats before installing them now.
(I'm not saying the product is bad. This is just a personal experience.)
  Just my 2 cents, Craig.

[mattyj858]

Just a heads up on the Mr.Gasket thermostat. I bought the same one and had it fail (stuck closed) on a test run. At the same time I found the factory gauge was not accurate....and I took out a head gasket on my 318-3 from the overheat. When I took it apart I tested the stat in a pan of water with a candy thermometer. The stat never opened in boiling water.
I try to check thermostats before installing them now.
(I'm not saying the product is bad. This is just a personal experience.)
  Just my 2 cents, Craig.

Yikes😲😲😲 hope that's not the case with this one!


So I installed the new thermostat and replaced the top and bottom hoses with radiator flex hose. The bottom 2" hose didn't have the wire coil inside but super rigid so hoping it's OK.


I have the part # for the upper hose but does anyone have a part number for the lower hose on a 73 440?


Ran the bago at idle for 20 minutes and the temp never got over 1/4 of the way, so hoping its all fixed. The true test comes under load, but it was dark and didn't want to put the tarp and cover back on (too lazy!). The pump is working good. I left the top radiator cap off until the the thermostat kicked in and the once full radiator became low as it circulated through the engine and saw good water flow with the help of a mirror over the radiator.


Thanks again everyone for all the help and insight!!!!! I hope all is fixed for now.

[roma]

I.ve followed the above discussion about overheating with great interest because every now and then I have the same problem with mine 413 engine.
I allready put in a new radiator with extra cooling core. Flushed the whole engine till the liquid became clean.
Changed the thermostat for a 185 degrees one. The right one for the industrial engine skirted.
Still the temperature stays unstable.
The only thing left to do is to change the visco fan.
I looked up all the numbers  I found on the forum but still not sure wich one I need.
Mostly that numbers say it wont fit on a 413-1 on there website.
Because I live in Europe I have to be sure to order the right one.
Can anyone help me out here to choose the right one


Greeetings Roma
Pride owner of a 73 winnebago Indian D24

[DaveVA78Chieftain]

Far as I know the information at this link is still valid.  Dodge P/N at NAPA still crosses to the same NAPA P/N.

[roma]

Dave ,thank you for the quick reply.
I  already used the information  you provided there. For some reason the napa site is blocked.
After some further trying I ended up with this part number wich seems to be the right one.Can you agree with that so I can start to order one.


Engine cooling fan clutch 4 seasons 36958  wich revers to part nr 771308.
The only thing different that it has no stud bolts to place the fan on but threades holes


Gr Roma

[DaveVA78Chieftain]

I did some research and the best I can come up with is that the 413 and the 440 both use the same fan clutch.  P/N info:
Hayden Heavy duty fan clutch P/N is 2747
4 Seasons 36956

Hayden Catalog

4 Seasons Catalog

Dodge P/N 3462182 New Old Stock

Dodge P/N 3462182 New Old Stock

[roma]

Thanks for checking out for me.
I am going to order one and will let you all know if it worked out fine.


Greetings from Roma   , Netherlands

[roma]

The viscofan has arrived.when I took the old one off something strange crossed my eyes.
As well as the pulley a the old visccofan are not centered by anything. Because the waterpump pulley is flat no axle pointing out in the middle. So both where only centered by the four bolts that tight the things together.


A in mine opion not very good and relaible way.
To fix it I made a teflon ring wich fitted in the pulley and fitted over the waterpump. So this one iis centered and on the pulley I fiited a smallaxle in the middle to center thefan.
So A lot of work on something that should have been there in the first place.

[Winnebago Warrior 94]

I might have missed something on the bar s radiator stuff ..when you added it ..did it circulate through your engine long enough? I was just curious if that could be why your engine over heated because it clogged up somewhere else if it didnt circulate long enough ..I dont know that for sure but just wondering if that could happen ..maybe after you ran it it unclogged ..our temp gauge wasn't working .we installed a new temperature sending unit ..then it started showing my engine was over heating ..we was freaking out ..lol..but them my hisband installed a new failsafe thermostat (they are suppose to stay open in case of thermostat failure ) but then my temperature gauge was still showing overheating ..then the,helpful people on this site helped us like they always do and we got a,heat temp gun and we performed test on the temperature sending unit and come to find out it wasnt over heating at all and the new temperature sending unit they sold us was either bad or not the,right one ..we got a new one and a different brand and haven't had any trouble ...fixed it right up..

[Rickf1985]

The viscofan has arrived.when I took the old one off something strange crossed my eyes.
As well as the pulley a the old visccofan are not centered by anything. Because the waterpump pulley is flat no axle pointing out in the middle. So both where only centered by the four bolts that tight the things together.


A in mine opion not very good and relaible way.
To fix it I made a teflon ring wich fitted in the pulley and fitted over the waterpump. So this one iis centered and on the pulley I fiited a smallaxle in the middle to center thefan.
So A lot of work on something that should have been there in the first place.

It sounds like the flange that the pulley mounts to was not pressed far enough onto the water pump shaft. I have seen that done to fix belt alignment issues. Definitely not the right way to do it.