Tiffin Allegro Bus doesn't start

[Mr_D]

Originally Posted by sirtate

It's likely the batteries.

As mentioned earlier; if the engine doesn't crank fast enough, it won't start.

Big diesels don't use glow plugs, they use the compression of cranking to ignite the fuel.
While a little automotive diesel will use a glow plug to heat the top of the combustion chamber, or a heater grid across the intake manifold to heat the air going into the engine, most heavy diesels don't.

They just spin them fast enough to make the heat by compression.

If your battery bank is weak you just won't have the ooomph to do the job when the ambient air is cold.

Have you tried it with a snort of ether? (That really is a two person job)

I have a 14.9L (922 ci) 650 hp ISX. As far as I know it has an air intake grid heater just like the ISC I had before.

[znt1186]

Your Cummins has a grid heater. DO NOT USE ANY ETHER! We were advised at Camp Freightliner that this would be a good way to forcibly remove the air intake manifold from the engine and deposit it a significant distance away from the rv.


You need to give the heater grid enough time to heat the air in the manifold before starting. It might take one or two cycles to get it warm enough to help the engine start. It would also help if you could get 110v to the coach either from shore power or the generator running to allow the block heater to be on for an hour or two.


Good luck.

[sirtate]

Originally Posted by Mr_D

I have a 14.9L (922 ci) 650 hp ISX. As far as I know it has an air intake grid heater just like the ISC I had before.

If it has a grid heater, is it working?

[oscarvan]

Originally Posted by sirtate

While a little automotive diesel will use a glow plug to heat the top of the combustion chamber, or a heater grid across the intake manifold to heat the air going into the engine, most heavy diesels don't.

They sure do. Cummins ISB 340 6.7..... Intake air heater..... "Wait to start" light.... watch the Volt meter do its windshield wiper imitation....... (Together with the "low charge" alarm going of 15 times.... most annoying)

[sirtate]

Originally Posted by oscarvan

They sure do. Cummins ISB 340 6.7..... Intake air heater..... "Wait to start" light.... watch the Volt meter do its windshield wiper imitation....... (Together with the "low charge" alarm going of 15 times.... most annoying)

6.7 ISB is a mere shadow of an ISX, and

There isn't any wait to start with the big ones at all. Even down below -20 Celsius (0F), turn the key and go. (Pending well charged batteries)
I lit one (15l ISX) off after 14hrs of cold soak, just Saturday morning at -15C... 4 cranks and away it went in a cloud of unburnt fuel. No block heater

[deandec]

Can you start the generator to charge the House batteries so the aux switch has more power behind it?

[HJLowell]

Unless you have at least 2 gauge.
And heavy duty clamps.
Most times your waisting your time and can overheat something.

[HJLowell]

Originally Posted by HJLowell

Unless you have at least 2 gauge.
And heavy duty clamps.
Most times your waisting your time and can overheat something.

[ATTACH]237524

These are what I carry

[RWDJR.]

Your house batteries WILL crank your engine if there is a charge in your chassis batteries. If the chassis batt is completely dead, it will need a charge to complete the circuit. The Aux button won’t put enough on it when there dead, only if there’s an enough charge on them when cranking. My NEW house batts will spin my 8.9 with no problem when my chassis batts get low. Yes my chassis batts are original, and the previous owners didn’t take care of the batts.

[Miramichi]

Spend $200 and get new starter batteries—-anywhere or call a tow truck, have it boosted for $150, then buy new batteries.