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marcvl · 01-04-2021, 01:14 PM

So, we did about 1,000 miles and average mpg came out to 7.66. From everything I've read, that seems to be reasonable for a 454 in a 345 motorhome, no?

Magnet18 · 01-04-2021, 03:18 PM

Yep, pretty average

Keyair · 01-04-2021, 03:23 PM

Your bathroom looks just like mine!
I believe the lid storage should be for dirty laundry.
Agreed, carpet is gross.
Storage is a problem on our motor homes... where your Dinette is I had a huge triple wardrobe... I ripped it out.
Several people have put a hinge on the wall next to the toilet allowing it to swing out... and give more space in the "Bathroom area".

marcvl · 01-05-2021, 07:01 PM

We did a compression test today and the results were pretty good: 170 psi per cylinder. Very little variation between the different cylinders. Spark plugs looked pretty clean.

Also, my mechanic confirmed that I don’t have air injection and no air pump. So I guess I got lucky with my smog test

Keyair · 01-05-2021, 07:37 PM

Awesome news!
On all fronts....

Put that engine replacement budget away for later!

marcvl · 01-10-2021, 04:31 PM

Yup. I decided to put the engine replacement on hold. I may still go ahead with re-coring the radiator to improve overall cooling (and reduce my stress level as I see the temperature gauge creep up).

I've been researching heating solutions. I currently have an operational Suburban SF-35 furnace, and two non-working Dometic 2928 hydronic boilers (re-badged Alde systems?). I could just get rid of the Dometic system, especially because it takes up an enormous amount of space (2 full cabinets left and right of the bathroom). But there is something appealing about hydronic air (no noise, works on 110V and gas, combined heat + water heater), and given that I already have all the piping and convectors all around the cabin, I could also install a new Alde Compact 3020 HE with the Alde Flow, and I would have hydronic heating, unlimited hot water, while still saving quite a bit of space.

The Alde system even has a heat exchanger that can sap heat from the engine and redirect it to the convectors all around the cabin. Pretty nifty.

Does anyone have experience with the old Dometic 298 and/or Alde systems? The previous owner tried to get the 298 back up and running, but he said the heating was insufficient to heat the entire motorhome. That's why he ultimately installed a Suburban instead.

Magnet18 · 01-10-2021, 10:15 PM

You might be the only one with an old alde system, certainly the only one I know of. I like your idea of retrofitting the old plumbing to a new unit, and keeping all the functionality. New unit is probably also smaller. I think that would be the ideal setup, and would do it if it didn't require such a huge upfront amount of work.

Keyair · 01-11-2021, 08:51 AM

Sounds like a very cool system!
Be a shame to rip it out, but if it’s taking up that much space....

Keeping these beasts cool here is Ca is a challenge. I think one of the things to do is reduce the Transmission cooling load on the radiator by having a large separate trans cooler.

bobmiller1 · 01-11-2021, 05:01 PM

Most of the motor home radiators run at 200 degrees or better. One if the reasons for this has been discussed before. The chassis when delivered to Airstream was only a chassis, engine, transmission, steering wheel and probably a milk crate for a seat. Airstream installed the AC compressor, therefore the factory delivered the chassis with a standard radiator and a standard 5 blade fan. When the transmission fluid enters the cooling coil in the tank of the radiator it is being heated or cooled to 200 degrees. The normal operating temp of transmission fluid should be around 170 degrees. In my opinion by deleting the transmission fluid from entering the radiator will not significantly reduce the coolant temperature. If anything routing the transmission fluid to an auxiliary cooler will not only make the transmission fluid cooler, it should bring it to it’s normal operating temperature if used with a temperature controlled fan on the auxiliary cooler. Although our front grills look [emoji41] (cool) they certainly restrict air flow from traveling through the AC condenser/oil cooler and all the other crap that Airstream added on in front of the radiator when they built these classics. Regards, Bob

Keyair · 01-11-2021, 05:29 PM

Good point Bob, and probably spot on as always!
For the record, my '87 3/4T Suburban had the the 454, dual AC option, and it had the 7 blade fan.... that fan is now on my Airstream, and boy, is it loud!

bkahler · 01-12-2021, 05:28 AM

Quote:

Originally Posted by Keyair

... and it had the 7 blade fan.... that fan is now on my Airstream, and boy, is it loud!

Sounds like your fan clutch may be bad.

Air345Fly · 01-12-2021, 06:11 AM

Perhaps the original fan clutch could not handle the 7 blade fan
and locked up. Is there a different clutch required the the 7
blade fan?

marcvl · 01-12-2021, 08:15 PM

What is currently considered best practice for improving cooling and keeping the 454 temperature in check?

dadstoy · 01-12-2021, 09:15 PM

Hey Marc,

It really comes down to one thing. You can spend money doing all the race car things and that will do nothing but spend your money. You can install electric fans, high volume water pumps, coolers for this and that.

That one thing is your radiator!

Pull the radiator and have it recored. Stock 4 core is all that is needed. Nothing more then that is needed except of course to make sure all other stock components are working; water pump, fan clutch, hoses, thermostat, belts. Run the stock thermostat. The engine needs to run at a certain temp to be efficient and the manufacturer has already figured this out.

From personal experience, use quality parts. Stay away from the Autozones and away from NAPA if possible. I personally changed the fan clutch three times. The third time I bought an OEM AC Delco part and that one worked. Its not fun to change the fan clutch three times. Same thing applies to temp sensors (I replaced twice before the quality one worked). Ask your shop who they get there parts from. I have had many customers (shops) purchase crap parts from Autozone. Make sure they get their parts from a quality parts jobber. Let them know you will pay the higher price for quality parts.

The radiator is the culprit!

bkahler · 01-13-2021, 09:10 AM

Quote:

Originally Posted by dadstoy

Hey Marc,

It really comes down to one thing. You can spend money doing all the race car things and that will do nothing but spend your money. You can install electric fans, high volume water pumps, coolers for this and that.

That one thing is your radiator!

Pull the radiator and have it recored. Stock 4 core is all that is needed. Nothing more then that is needed except of course to make sure all other stock components are working; water pump, fan clutch, hoses, thermostat, belts. Run the stock thermostat. The engine needs to run at a certain temp to be efficient and the manufacturer has already figured this out.

From personal experience, use quality parts. Stay away from the Autozones and away from NAPA if possible. I personally changed the fan clutch three times. The third time I bought an OEM AC Delco part and that one worked. Its not fun to change the fan clutch three times. Same thing applies to temp sensors (I replaced twice before the quality one worked). Ask your shop who they get there parts from. I have had many customers (shops) purchase crap parts from Autozone. Make sure they get their parts from a quality parts jobber. Let them know you will pay the higher price for quality parts.

The radiator is the culprit!

What Dean said. Re-core the radiator.

marcvl · 01-13-2021, 11:32 AM

Quote:

Originally Posted by bkahler

What Dean said. Re-core the radiator.

Re-coring it is! Dropping her of next week. Besides the radiator, the brakes need work (leaking oil), the rear shocks need to be replaced, and an exhaust leak fixed. Also the upper radiator hose keeps collapsing. We put in a new hose and replaced the coolant reservoir cap but it keeps on happening.

marcvl · 01-18-2021, 05:43 PM

I’m working on replacing, rewiring, and automating all overhead lights. Gosh, it’s pretty difficult to get these white plastic covers off. I would like the lights to be dimmable, support RGB colors in addition to white, and be controllable through an app.

So, here’s my plan:
1: replace all 6 lights in each overhead section by identical warm white LED lights. Wire them all in parallel ( and replace the “high/low” switch with a simple on/off switch)
2: add an RGB LED strip (“party mode”)
3: install a Shelly RGBW controller inside the same light fixture which allows me to continue to control the lights with a switch, but in addition gives me more sophisticated app-based control.

I found a spare light fixture, so I’ll experiment on that first. Should be fun!

Magnet18 · 01-18-2021, 09:49 PM

Excited to see how it turns out!

Waipio Rim · 01-19-2021, 10:15 AM

This will be my cooling system manual when the time comes:

http://theouterlimits.ws/projects/ai...e_cooling.html

The author was a member who passed away, but his website is still up.

Magnet18 · 01-19-2021, 01:59 PM

Quote:

Originally Posted by Waipio Rim

This will be my cooling system manual when the time comes:

http://theouterlimits.ws/projects/ai...e_cooling.html

The author was a member who passed away, but his website is still up.

Waynes work was fantastic, I referenced his site regularly during my efi install, and I have a copy of the whole site downloaded just in case it ever goes offline.