Oil Changes and Overheating- A Cautionary Tale

[Rambow]

Last year I began experiencing persistent overheating of the 6.8 liter V10 on my '99 Southwind 36Z. My mechanic, himself a motorhome owner, started by replacing the least expensive component first - the thermostat, then flushed the coolant. No joy. We advanced through a new water pump and fan clutch, and still there was no improvement. Finally, in desperation, I ordered a new radiator and as soon as the mechanics dropped the old radiator out the bottom of the coach the cause became immediately apparent.




The less than stellar diagnostic skills of my mechanic aside, my main reason for posting this tale is to save other owners from a similar, expensive experience.

Because I have always done my own oil changes, ultimately, I was the cause of this problem, with a some help from the designer of the ridiculous placement of the oil filler tube in the F53 chassis. It is hard against the firewall with only about six inches of overhead clearance from the horizontal overhead. It is almost impossible to get a funnel into the tube and pour quarts of oil into it without slopping a little oil over the side. After discovering this, I made it SOP to drape an old towel below the filler tube to prevent the inevitable spills from falling on the radiator, transmission cooler, or air conditioner condenser. But over the last 16 years, since we bought our coach new, it's obvious from the thoroughly caked radiator that my preventive measure was ineffective, to say the least! I should add that the radiator is well hidden behind the aforementioned components and is extremely difficult to inspect. The visible portions of the radiator looked fine.

To protect my shiny new radiator from a repeat performance I bought a funnel emptying into a hose that can be shoved well down the filler tube, and long enough that the funnel itself can be filled outside the coach. The one I have was purchased at Walmart and is shaped like a large measuring cup. It holds a full quart of oil, has a built-in filter screen, and a twist valve to stop the flow. The plastic tube it came with was too short and so thin that it tended to kink, so I replaced that with a four foot length of nylon-braided, clear vinyl water hose from the plumbing department of Home Depot.

Now, with the funnel's handle shock-corded to the windshield wiper base, which puts it higher than the top of the filler tube outside the coach, I can pour from a 5 quart oil jug. Care must be taken when removing the hose from the filler tube as there will still be some oil in the hose where it hangs below the filler and funnel, but a rag over the end takes care of that until it's out from under the hood and can be drained back into the oil jug.

If you trust someone else to do your oil changes, beware. I doubt if he'll be very cautious about a few drips of oil. After all, in most vehicles the filler tube isn't in such a treacherous position, and a rag will take care of a little spillage.

Now, go forth, my brothers and sisters of the road, and drip no more.

[JumboJet2]

It was a slow and painful process, but I used a mechanical pump to add the new oil. I know what you mean by difficult to add oil with the setup in place.

[jergeod]

If you pull the engine cover inside look at the right valve cover you will see a hose that goes to the cover, remove the hose then use a trans funnel to add your oil, no mess no fuss very easy.

[Rambow]

Hi George. That's a good alternative I never would have thought of. With my old knees, though, I think I'd rather do the task standing up. Getting up and down toward the end of the task to run outside to check and recheck the dipstick makes my knees ache just thinking about it. You are also assuming I would not drip oil on the carpet! I'll leave this method to the younger, less sloppy owners.


Semper Fi

[McFarlin AZ]

Originally Posted by Rambow

Last year I began experiencing persistent overheating of the 6.8 liter V10 on my '99 Southwind 36Z. My mechanic, himself a motorhome owner, started by replacing the least expensive component first - the thermostat, then flushed the coolant. No joy. We advanced through a new water pump and fan clutch, and still there was no improvement. Finally, in desperation, I ordered a new radiator and as soon as the mechanics dropped the old radiator out the bottom of the coach the cause became immediately apparent.





The less than stellar diagnostic skills of my mechanic aside, my main reason for posting this tale is to save other owners from a similar, expensive experience.

Because I have always done my own oil changes, ultimately, I was the cause of this problem, with a some help from the designer of the ridiculous placement of the oil filler tube in the F53 chassis. It is hard against the firewall with only about six inches of overhead clearance from the horizontal overhead. It is almost impossible to get a funnel into the tube and pour quarts of oil into it without slopping a little oil over the side. After discovering this, I made it SOP to drape an old towel below the filler tube to prevent the inevitable spills from falling on the radiator, transmission cooler, or air conditioner condenser. But over the last 16 years, since we bought our coach new, it's obvious from the thoroughly caked radiator that my preventive measure was ineffective, to say the least! I should add that the radiator is well hidden behind the aforementioned components and is extremely difficult to inspect. The visible portions of the radiator looked fine.

To protect my shiny new radiator from a repeat performance I bought a funnel emptying into a hose that can be shoved well down the filler tube, and long enough that the funnel itself can be filled outside the coach. The one I have was purchased at Walmart and is shaped like a large measuring cup. It holds a full quart of oil, has a built-in filter screen, and a twist valve to stop the flow. The plastic tube it came with was too short and so thin that it tended to kink, so I replaced that with a four foot length of nylon-braided, clear vinyl water hose from the plumbing department of Home Depot.

Now, with the funnel's handle shock-corded to the windshield wiper base, which puts it higher than the top of the filler tube outside the coach, I can pour from a 5 quart oil jug. Care must be taken when removing the hose from the filler tube as there will still be some oil in the hose where it hangs below the filler and funnel, but a rag over the end takes care of that until it's out from under the hood and can be drained back into the oil jug.

If you trust someone else to do your oil changes, beware. I doubt if he'll be very cautious about a few drips of oil. After all, in most vehicles the filler tube isn't in such a treacherous position, and a rag will take care of a little spillage.

Now, go forth, my brothers and sisters of the road, and drip no more.

Yup,

I get the hassle. I had exactly the same issue on my DP as to location of filler tube Didn't want the hassle of lifting and propping the master bed to access the engine compartment to fill at the head cover. Who wants to have 5 gallons of oil in their bedroom subject to spilling?!! I am not the most agile guy any more so I did what you did and have an extended funnel outside the coach. I also do my own changes on just about everything I can reach BUT the coach was used when I bought it and was overheating under load.
Needless to say I chased everything I could trying to correct the problem and found the same issue as you. Chassis manufacturers are notorious for installing slobber tubes to short for MH application and a DP sucks everything from road grime and rain splatter to oil from your slobber tube and spews it all over everything. As it is with DP, the fan pushes air rather than sucking air through the radiator effectively plugging it up from behind and out of sight.
Couple gallons of SuperClean later and many rinses, I now can travel without overheating. Capturing the mess is the hardest part.

Mike and Cynda along with co-pilots Toby, Sadie and Cody, the best 4 legged kids a guy could want!
'05 Alfa Founder 36FS, Cat C7, Allison tranny and FL chassis.
Happy trails buddy!

[mojoracing]

I too do my own oil changes. I use a similar funnel also pursued at Walmart. I tried the fluid transfer pumps and they weren't worth the effort and cleanup. Between the funnel and the fumoto valve I installed, an oil change is a 15 minute proposition.

[Billinwoodla]

OK, sorry, but I am missing something here. So is the picture showing occluded fins? Did the oil clog up the air movement through the radiator?

[Waiter21]

I found similar on my 2001 Mirada, but nowhere near as bad as what you have in the photo. I seen it on the A/C condenser and used the power washer to clean it. I'll need to get in there and look at the radiator and see what it looks like.

Thanks for the heads up

[429CV23]

Originally Posted by Billinwoodla

Did the oil clog up the air movement through the radiator?

No. Technically the dust, dirt, bugs, etc. that were deposited and held by the oil, and packed into the radiator fins by air pressure reduced the flow of air through the radiator, thus reducing its efficiency/ability to cool the engine.

[sirpurrcival]

Originally Posted by jergeod

If you pull the engine cover inside look at the right valve cover you will see a hose that goes to the cover, remove the hose then use a trans funnel to add your oil, no mess no fuss very easy.

That is the way I do it as well. I presume that the filler spout on the forward side of the firewall is really aimed at shops that have filler hoses. There is no easy way to get a conventional funnel into it.

[Rambow]

Originally Posted by Billinwoodla

OK, sorry, but I am missing something here. So is the picture showing occluded fins? Did the oil clog up the air movement through the radiator?

Yes. It looked as if someone had taken tar and painted it on a third of the radiator fins from top to bottom so the air flow was cut by that amount. The only time the engine did not overheat was in cold weather. With one third of the radiator's fins and tubes sealed in this glutinous mess of oil, dirt, and bugs, there just was not enough cooling surface left to do the job.

[charliej]

Thanks for the tip. I've tried using a dixie cup, hand pump the did not fit the oil bottle. Will try this, sound good. With this and my new drain valve it should be a lot quicker.

[LETMGROW]

Originally Posted by Waiter21

I found similar on my 2001 Mirada, but nowhere near as bad as what you have in the photo. I seen it on the A/C condenser and used the power washer to clean it. I'll need to get in there and look at the radiator and see what it looks like.

Thanks for the heads up

A word of caution. Be careful with the pressure washer.
Last summer I had a customer come in to my shop with a newer Dodge pickup with an overheating problem. The engine would run normally at idle and low speeds but at highway speed under a load the temp. needle would climb into the red zone. The customer told me he started having this issue right after cleaning the engine and engine bay with his new pressure washer. He had bought a high pressure washer for cleaning buildings etc. Nice unit, I might add.
We found the fins in the A/C condenser were blown flat from the high pressure water which effectively shut off air flow to the radiator sitting behind it. After about an hour straightening the fins the air flow was restored and the overheating problem was solved.
Lynn

[donhoward49]

Great ideas here.. How about a picture or two of the fancy oil funnels..
Thanks