How many of us are there? Owners of Dodge based RV's?

[whiteknight001]

I'm new here, and curious.

How many of us in Class C own Dodge B300 incomplete
cab/chassis based RV's? I know two others- Steve aka
Ripsaw, with a 1977 Brougham, and Leroy aka 1978_Dodge
_Delta who owns a 440V8 powered sharp looking 1978
Delta RV. I would like to ask, and offer, help, idea
swapping and comparing notes on our particular RV's
which are based on the Dodge B300 van chassis.

Yeah, I know. These are low tech, podgy old RV's that
would be considered "entry level" for folks like me,
but I have a deep and abiding respect for the quality
of these old "monsters of the open road". And anyone
wanting to pick brains, joke about, share notes or just
brag about our old A- Dodge-io's are certainly welcome
to PM or email me. Between all of us we can form a real
good support group, and help each other with problems
we know we'll encounter with an older vehicle.

Sure. I'd love a new RV. But I'd rather have an older
one already paid for, and a lotta great memories. Call
me frugal, an old hippie, or whatever you will. I'm proud
of my old land yacht.

Mopar Madness Manifest in the flesh,

Mark aka White Knight

P.S. Mine's a '72. Is there an older one out there someone's
motorvating in? Maybe even a Travco? W/K

[Griff_in_Fairba]

eyeteeth wrote:
I usually look for engine parts in the '78 range. But he dash design, and quad headlights are from '79-80... makes this all that much more difficult.

It does have A/C... not that it works... but the parts are still there.

Changed oil and filter a couple weeks ago. Pressure seems a little low. The gauge is just barely under half.

Yea, the blocked passage definitely would not be nice. I wonder if a 'flush' would clear that.

Oil pressure is okay ... that's where the needle usually is. (Plus, dash gauges aren't all that accurate ... a corroded or loose connection between the sensor and gauge would cause a lower reading.)

Engine flush is a definite recommendation. You might even want to do two or three.

Find a reputable radiator shop and ask if they can do a more thorough flush.

Headlights and dash are a clear indication the chassis is a 1979.

I have a CarQuest commercial account, which gives me access to the same data as the counter people.

In your case, look up parts for 1979 CB300. The main difference between a MB300 and a CB300 is the factory had passenger seat as standard in MB300 and optional in CB300. There may be other minor differences but the two chassis were effectively identical.

Looking up parts for 1978 CB300 is okay as long as you keep the possibility of differences in mind and compare old parts to new parts. Most of the changes between the two years was probably cosmetic, with engine, drivetrain, suspension, etc. probably identical.

The CarQuest listing for '79 CB300/440 didn't include lower radiator hose. (GRRRRR!) So, I went to the '78 CB300/440 listing and crosschecked to verify the likelihood of correct parts.

Upper radiator hose, with A/C, for both is C70461 or 81161

Lower radiator hose, with A/C, for '78 is C70438 or 813321

(First number is OEM style cut-to-fit hose and second is suitable flex hose.)

No radiator cap listed for '79 CB300/440. (Double GRRRRRRRRRR!!!) Only cap listed for '78 CB300/440 was a Mr Gasket aftermarket, with built-in thermometer (?? ... and more expensive), P/N 2476BK. Crosschecked with '78 B300/440, which showed same cap plus OEM style caps by Stant. (Less expensive and, in my mind, preferable.) Stant standard cap is P/N 10231 and with pressure release lever is P/N 10331. Pressure rating for all these caps is 16 PSI.

Also crosschecked radiator cap for '79 B300/360 and same numbers were listed.

[eyeteeth]

I usually look for engine parts in the '78 range. But he dash design, and quad headlights are from '79-80... makes this all that much more difficult.

It does have A/C... not that it works... but the parts are still there.

Changed oil and filter a couple weeks ago. Pressure seems a little low. The gauge is just barely under half.

Yea, the blocked passage definitely would not be nice. I wonder if a 'flush' would clear that.

[Ballenxj]

Griff in Fairbanks wrote:
It looks like Dodge did away with the 440 engine in everything except the CB300 in the 1979 model year. (Checked B300, D300/400/450, and W300.)

I know of a person that has a B class that is 1980 vintage, and this person says it came equipped with the 440. Might be another place to look.

[Griff_in_Fairba]

It looks like Dodge did away with the 440 engine in everything except the CB300 in the 1979 model year. (Checked B300, D300/400/450, and W300.)

You may have a split year motorhome, titled as a 1979 but built on a 1978 or even a 1977 chassis.

Can find listings for OEM spec hoses for you but need to know A/C or non-A/C

[Griff_in_Fairba]

With or without A/C?

Found a CarQuest OEM spec hose but only for A/C ... otherwise, listings for generic flex hoses for both A/C and non-A/C.

Will check other years to see if there was a change ...

[Griff_in_Fairba]

One more thing ... do you have fresh engine oil and sufficient oil pressure?

Most people don't realize engine oil plays a crucial role in helping to keep the engine at the right temperature.

If none of this identifies the problem, it's likely a key coolant passage in the engine has become blocked. It's not unheard of for engine rebuilders to fail to clean the block completely, leaving junk in the passages that can become dislodge and subsequently block a key passage. (I know, not good news ... especially because this tends to show up after the engine is past the warranty period.)

[eyeteeth]

It is titled as a '79.

I'm always a little scared of fans and spinning belts. Especially being a longhair.

[Griff_in_Fairba]

Yup, that's the correct orientation for both thermostats.

Actually, the fan clutch is supposed to release at higher speeds, when airflow through the radiator is sufficient without the fan turning. If it doesn't release, it could create drag on the water pump, causing insufficient coolant flow.

Try using belt dressing on the fan belt and see if that helps any. (Belt dressing increase friction between the pulley and belt ... a stuck fan clutch could cause the belt to slip in the fan pulley.)

The radiator cap for the same year/engine B300 van should be correct.

To check the lower hose, bring the engine up to temperature at idle and, while watching the hose, have someone bring the RPMs up to a steady mid-range, about 3000 RPM. Hold it steady there for a few minutes and watch if the hose starts to collapse. BE VERY CAREFUL to make sure the vehicle doesn't move while you're down there watching the hose. Also, BEWARE of the fan ... it's basically a whirling set of knives.

Most lower radiator hoses have springs inside the hose or metal rings embedded it the rubber to keep them from collapsing. I'd need the year to look up the correct hose. (19xx/B300/440).

As a rule, if I can't find an OEM spec hose, I use non-specific hoses with the ridges along its length ... those are more resistant to collapse.

BTW - high performance water pumps aren't really necessary in anything other than race engines and constant desert operation.

[eyeteeth]

Thanks for the quick responses.

I'll check into the cable. I will more than likely bypass the cruise control. I had a custom one made a while back by Southern Speedometer but it didn't quite fit right, and eventually broke.

"Over the years, I've seen two cases where the thermostat was installed upside down. The "wax" capsule, usually copper colored, needs to go down, into the coolant."
- I'm going to assume the current thermostat is installed correctly as it would only fit/work one way, with the skirt facing down.



"Your fan belt may be slipping at higher RPMs."
- Felt tight when we checked

"Some high performance water pumps have more vanes ... if I recall correctly, eight vanes versus standard six."
- Not sure I'm up to taking it apart.....

"If your fan has a clutch, the clutch may be malfunctioning."
- The clutch is relatively new as well. Seems to be functioning properly. The fan is turning when the engine is hot...

"Is your lower radiator hose in good shape? Suction at higher RPMs may be causing an old/soft hose to collapse, restricting coolant flow."
- That might be a possibility, This too is fairly new. I replaced it a few years back when I had the radiator recored due to leaks. However.. it does seem a little 'soft' to the squeeze. I'm sure it gets worse as the temperature rises. Perhaps a correct part number for this part. I had to adapt a lower hose before. Found something close and cut it to fit.

"Conversely, a partially blocked upper hose could allow enough flow at low RPMs but not enough at higher RPMs."
-Upper hose is good.

"Make sure the radiator cap fits properly and has the right pressure rating. A new cap costs less than $10 and is cheap insurance. (I often replace them just to be sure.)"
-I knew I forgot something at the store earlier today. Perhaps another trip is order. As the RV is not here. What pressure cap do I need? I feel like I bought one of those a while back as well.

"Does your radiator steadily lose coolant? A radiator without an overflow recover tank will have some air space at the top, with the air acting as a pressure cushion. However, the core should remain completely immersed."
-No. New core a couple years back. Has a recovery tank... although I was going to check to make sure there was sufficient coolant in the recovery tank.

"Finally, your engine temp sensor or gauge may be giving incorrect readings."
- I hit it with one of our racing laser temp guns.... its definitely hot.

Thanks for the checklist.

[Griff_in_Fairba]

TreeSeeker - excellent response to goreds2's question. I liked that you pointed out problems with 120VAC to 12VDC converters in older motorhomes. I also liked your description of a preliminary diagnostic step as a means for goreds2 to possibly answer the question.

When I get unbusy, I plan to resume my discussion of batteries and charging systems. (The same with kingpins ... but, it's summer and I need to work on the house when it's not pouring down liquid sunshine.)

[Griff_in_Fairba]

Oh, yeah ... speedo cable ...

Lokar is a good place to start. There is a place that makes cables for older vehicles, such as the cables for old pushbutton A727 transmissions, but I can't seem to find the link for their site.

Assuming you have a Class C, a B100/200/300 van cable should fit. Class A's often have different cables due to difference in cab manufacture but Class C's have the same cab as vans, with the same distance between the instrument cluster and tranny speedo gear.

Unless you really, really want cruise control, do what Leeann suggests and go with a standard non-cruise cable. (Older cruise controls tend to be problematic due to being mechanical mechanisms rather than the newer computer controlled electronic systems ... I usually chuck cruise controls on older vehicles.)

[Griff_in_Fairba]

I'm with Leeann -- sounds like something is preventing full coolant flow at speed.

The reverse of your situation is typical, with overheating occurring at low RPMs and going back to normal as RPMs increase.

Over the years, I've seen two cases where the thermostat was installed upside down. The "wax" capsule, usually copper colored, needs to go down, into the coolant.

Your fan belt may be slipping at higher RPMs.

Some high performance water pumps have more vanes ... if I recall correctly, eight vanes versus standard six.

If your fan has a clutch, the clutch may be malfunctioning.

Is your lower radiator hose in good shape? Suction at higher RPMs may be causing an old/soft hose to collapse, restricting coolant flow.

Conversely, a partially blocked upper hose could allow enough flow at low RPMs but not enough at higher RPMs.

Make sure the radiator cap fits properly and has the right pressure rating. A new cap costs less than $10 and is cheap insurance. (I often replace them just to be sure.)

Does your radiator steadily lose coolant? A radiator without an overflow recover tank will have some air space at the top, with the air acting as a pressure cushion. However, the core should remain completely immersed.

(The moose eliminated the overflow recovery tank from our van so the van loses some coolant over time. We just have to be careful to check the coolant regularly to make sure we haven't lost too much.)

Finally, your engine temp sensor or gauge may be giving incorrect readings.

If all these things check out okay, then your radiator is partially plugged and needs to be taken to a radiator shop for cleaning or re-core. (Radiator shops are the only places that can really do an acid flush because the radiator needs to be out of the vehicle.)

[Leeann]

Sounds like the water pump is suspect or your cooling passages are clogged. I don't think it requires something special, but I got ours from our local parts house. I deal with a guy there that knows old Mopars, plus I have the parts manual so we cross the numbers. But most just he just knows off the top of his head.

Speedo cables, I have a link to Lokar:
http://www.lokar.com/product-pgs/throttlecables-kickdowns/tc-kd-pgs/throttle-cables.html

If I remember correctly, though, my local guy got me the right one for ours (I brought in the old and he matched it). Our cruise control, which is an add-on and not factory, has never worked properly so I think we just bypassed it.

[eyeteeth]

Griff & Leeann... calling on your expertise.

So starting to run out of things to try and check.

Overheating... running hot.

In 2013, the Waterpump went out and was replaced. Around 2009 or so the engine was rebuilt. Maybe 10-12,000 miles at most with the rebuilt motor. Last fall I did replace the thermostat, Found out it had the wrong one installed. I did track down and install a 180 degree skirted thermostat. I'm wondering if maybe the 440-3 engine that is in the RV requires a special part for the water pump as it did with the thermostat.

About the only thing I have found online for a resolution to my problem was someone who used some acid based flush that solved the issue.

It idles OK, seems OK until I get up to high way speed.. starting about 50mph, the temp climbs.... from about 3/4 5/6 gauge upward.

I want to travel a few places yet this year but am having problems getting out of town. Any ideas or questions for me?

Second item... Speedo cable. It came with some cruise control on it. IT worked back in 2007, doubt it works any longer. Don't think I need to try and keep it in line... so single cable that goes to the tranny would be fine. Unless you may know what to get for the cruise control module.

That's a couple starter questions...

[goreds2]

OK - thank you,