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Topic: 1991 U300-- bought it! (Read 9382 times) previous topic - next topic

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #60 –
Quote from: steve31 –
...... Last keep an eye on that rear radiator and make sure it's as clean as you can. Every year douse it with full strength Simple Green ( from inside and outside with garden sprayer). Hot water rinse down. If your careful you won't have to spend an hour cleaning up the bedroom. You'll be stunned how much stuff you flush out. The things that can kill your DD is low oil pressure and heat. Keep up on those and that motor should last you your natural life. 

Excellent recommendation, however, I would use
use this over regular Simple Green. It was first recommended to me by a local radiator shop.
Amazon.com: Simple Green Extreme Aircraft and Precision Cleaner, 1 Gallon...
As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #61 –
As Steve says, watch the low oil pressure and don't overheat it like all wet sleeve engines. After pumping at a fire our Detroits would not have that much oil pressure at idle. One of several reasons we never idled them for very long. The fast idle switch on the dash brought the idle RPM up from 600 to 1000. This speed circulates coolant much better, brings the oil pressure way up and cools the oil, especially important with turbos. Foretravel Detroits don't have a fast idle switch and the cruise control does not work for that so it's up to the operator and their foot.

Unlike most wet sleeve engines, the 92 series only has a 2 inch area that is exposed to the coolant but the sealing rings at the top and bottom of the sleeves don't like to get overheated. Overheating and cavitation can cause pitting on the outside of the sleeves and eventual erosion.

Pierce

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #62 –
<snip>

Check the air filter and replace with the Donaldson pictured. A hole needs to be punched in the end so the restriction gauge will work.

PM for more info.

Pierce
[/quote]

Hi Pierce.

Where do I punch the hole that you mentioned?

Thanks,
Jeff

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #64 –
Quote from: Jeff & Sandy –
<snip>

Check the air filter and replace with the Donaldson pictured. A hole needs to be punched in the end so the restriction gauge will work.

PM for more info.

Pierce


Hi Pierce.

Where do I punch the hole that you mentioned?

Thanks,
Jeff
OK, you can see the rubber/foam gasket that you removed from the old filter so you just punch a hole anywhere on the inside. I had a sharp punch and just tapped it with a hammer.

The big problem with GVs is the air intake location right behind the right rear duals. Anything thrown back by the tires is sucked in, dust, dirt, leaves, twigs and water. It's worse on the 2 cycle Detroit as it uses twice as much air as a 4 cycle plus the big blower has great suction power, so much in fact that it partially collapsed the old air cleaner. The construction on the Donaldson is much more robust and there are more places a glue has been applied.

Not sure if the rear radiator U300 air cleaner is the same part number as the later side radiator U300 models.

If you are wondering why the 1991 has 50 less horsepower, it's because HT746 transmission was not available to Foretravel and then MTB648 Allison was not rated to handle the 350 hp along with the torque the 6V-92TA produces so the engine was derated. It's just in the DDEC IIs ECU so a firmware update will raise the HP to the max allowed by the EPA for the street. (fire trucks excepted)

Attached photo shows the hole I made in the air cleaner two changes ago. Watching the restriction gauge is important as it really increased the power in ours the first time I changed it. This is especially important for 4 cycles as a restricted air cleaner may cause excess fuel to be delivered, even more so at altitude causing high EGTs. Also attached is the maximum restriction for each brand of engines.

Pierce

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #65 –
Why do I remember a cruise control fast idle?

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #67 –
Sure thought the Detroit's had a fast idle somewhere? 

Re: Thinking of purchasing this 1991 Grand Villa, worth it? (Bought it!)

Reply #68 –
Some more updates.

With @stump help, I am able to fix the leak and move the bus back and forth for a little bit.

So Tuesday, @stump helped me find the source of the leak. It is pin hole at the bottom of the rear air tank

Wed.
I followed @stump  suggestion to use self taping sheet metal screws and a washer to seal the tank.
I used some drills to drill the hole to get rid of some rust. However under the bus with very limit space, I drilled the hole too big. The largest sheet metal screw is 1/4in. It barely stay on the hole. I wrapped around some teflon tape so it can stay little bit tighter.
Then use #80 sand to smooth the nearby sufface
Use 3 worm clamp to hold the screw in place.
used JB-Weld steel enforced epoxy to seal the screw and the clamp.
It looks messy, but it should work.

Thur.
After the epoxy is fully cured. I went under the bus to check the air tank. The epoxy feels rock solid. So it should hold some air pressure.

So I first hook up the shore powered air compressor, it is able to build some air pressure to keep the air bag inflated. With the little air compressor running, I checked around, didn't hear any leaking sound. Good sign!. But the air bag still not aired up the bus.
So I try to start up the big engine. And of course the battery died due to lack of charging for the past few days. How frustrating!
So switch to new battery, start the engine. I am excited to see the air pressure gauge is moving. It is building air pressure. But it stops at 30PSI. Not able to air the bus up. Very frustrated.

This time, I can hear the air is leaking from the shore power air compressor. More specifically the left cylinder. So I need to fix the leak. Tracing the hose, there is one hose come from the tank to the shore power air compressor, so if I terminate that hose, then I should be able to by pass the little air compressor. Went to Lowes, they don't have fittings for 3/8 OD hose. Went to NAPA, bought the fittings to terminate the hose. And this time the air is up to 90 PSI!

It takes a while for all 8 air bags to be inflated. After 20 minutes, all air bags are inflated. Following @stump instructions over the phone, I put the three level switch in the middle to switch from level mode to ride mode.
Release the parking brake.
Hold the brake pedal, then put the transmission in to D, the transmission engaged! After a little put accelerate pedal, the bus moved forward for a few inches. Then put in R, the bus moved back a few inches.

For the first time in at least 15 years, the bus moved! What a moment!

After little excitement, new issues show up. After the brake pedal, the air pressure is not building up anymore. It stays at 10PSI. New problem! Luckily, at this time @stump is on the phone with me. Otherwise, I will already suffer few heart attacks. :) He quickly point out the air governor is probably of no good.  He instructed me to use some hammer to see if I can loose the piston. No good. The governor is connected with two hose and two bolts, with @stump encouragement, I am able to take the governor off and run to NAPA store 5 minutes before they close :o
The original governor works at 95-105PSI. NAPA doesn't have that parts in stock. But they have 105~125Psi. With @stump approval, I bought that one and installed back on the engine compressor. Checking the old governor, it is all filled with rust. No wonder why it is not producing air pressure any more.
With the new governor, the engine can build up air pressure up to 120PSI pretty easily. 
I found another leaked hose in the shore power compressor bay. It is the 1/4 hose. Plan to splice using the quick air fittings tomorrow.

More thing to do later,
Install new 3/0 battery cables to connect the house batter. Old one rusted out.
Change all six tires. Tire shop will come to change on the spot.
clean the water tank as much as possible to get rid of the smell.
Change engine oil, coolant, transmission fluid, all filters
Startup the generator. and oil / filter of the generator


All of this happened while @stump is on the phone with me. I am unable to handle all of this by myself. His knowledge on the bus is unbelievable. I have no doubt that he can fix anything around the bus.

@stump, Thank you!


Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #70 –
Stump is awesome.

Re: Thinking of purchasing this 1991 Grand Villa, worth it?

Reply #71 –
Quote from: Caflashbob –
Sure thought the Detroit's had a fast idle somewhere? 
Bob,

You were probably thinking of the fast idle on the ProLink 9000 used to test the injectors. If you don't do the injector test, you can stop one step early and fast idle at exactly 1000 rpm.  The ProLink warns you at least twice to make sure you are in neutral as the Detroit develops a lot of torque at fast idle and will overcome the brakes. For those not familiar with the ProLink, it reads the engine's computer for history, codes, mpg for a total of about 45 items plus it tests and can change certain operating parameters. Still available on the used market with cartridges for most electronic engines, transmissions and ABS brakes.

Our Detroit powered fire trucks were all manual transmission so that was not a problem so all had a fast idle switch.

Pierce

Re: 1991 U300-- bought it!

Reply #73 –
I thought the fast idle was part of the cruise control stalk on the steering column.  Anyone have the owners manual from Foretravel?

I maybe wrong but I think I remember demoing the fast idle many times.  Maybe the cat?  At least the early u300's?

Birds had a fast idle switch on the dash. 

Re: 1991 U300-- bought it!

Reply #74 –
Detroit's don't have the option of cruise control for high idle.

Re: 1991 U300-- bought it!

Reply #75 –
Engine running.  Trans in neutral. Slide the cruise control button to the on position and slide it past the on position  and briefly hold it in that position.  Does the idle go up?

Re: 1991 U300-- bought it!

Reply #76 –
Works on Cummins rigs, not our Detroit. Tried it years ago when the topic came up. Perhaps it does work on a early U300 but not ours. Any other Detroit owners able to get fast idle?

Pierce

Re: 1991 U300-- bought it!

Reply #78 –
You also need new air cleaner. On my 91 6v92 it is a wix 56726. Donaldson does not make one anymore for our coach (xlp18-2990)

Ken

Re: 1991 U300-- bought it!

Reply #79 –
You also will have a retarder on the Allison not a Jake like the next year. As I remember, when the 648 Allison shifts, it does not lock up in the same gear as the 746 Allison. Perhaps a "91 U300 owner can go over the retarder and the lockup shifting sequence here.

Pierce