Service bulletin for improving Robin engine starting

[Marks481]

I never saw this one, but it is interesting:

http://www.jackssmallengines.com/pdf_documents/robin engines/Manuals/RA-SB-015.pdf

It says that the Robin engine may be difficult to start because of parasitic loads such as hydraulic pumps in cold weather. Sounds kind of familiar.

It recommends swapping out the oem starter motor for the heavy duty version that Faztrac is currently looking at replacing on another thread.

It also swaps out spark plugs and starter coils. It says it applies to 2002 models, but I suspect that the later models might also have the weaker "HD" starter motor and ignition coils.

 

[Gravy]

I never saw this one, but it is interesting:

http://www.jackssmallengines.com/pdf_documents/robin engines/Manuals/RA-SB-015.pdf

It says that the Robin engine may be difficult to start because of parasitic loads such as hydraulic pumps in cold weather. Sounds kind of familiar.

It recommends swapping out the oem starter motor for the heavy duty version that Faztrac is currently looking at replacing on another thread.

It also swaps out spark plugs and starter coils. It says it applies to 2002 models, but I suspect that the later models might also have the weaker "HD" starter motor and ignition coils.

According to JackRobin (I miss him) my 2004 came with the updated coils and spark plugs. He sent me the heavy duty starter at no charge. It helped a bit, but the difference wasn't dramatic. I wouldn't expect too much.

 

[BobRip]

I have done it on my 2000 PT422. I don't see a big difference, but my PT is stored in a heat garage.

 

[Marks481]

I will have to check the starter motor number on my 2005 model. But with Gravy'sreport that the different starter didn't make much difference, I might not bother.

I wonder how much room a clutch would take to install?

Actually, I bet the bestway to improve winter starting performance would be to figure out how to shoehorn a group 24 (full size auto battery) into the engine compartment. The little garden tractor battery just doesn't seem to have enough cold cranking amps... and it is a fairly new battery. AnytimeI needto start when it is less then 40F, I have to put the charger on it.

 

[Clumber]

Tim,

The battery that came with my new PT 425 is 2/3 size of a car battery-- should be sufficient and easier to fit. See photo.

 

[BobRip]

I put an Optima yellow top in mine. It's the same size that fits some Hondas. 450CCA. I keep it on a float charge. This will help.

 

[Gravy]

My PT425 has a Honda car size battery - maybe a Group 41 if I remember right. There is no other common automotive battery size that will fit the narrow space. I've looked at the higher tech batteries such as Optimus, but I haven't found a higher capacity battery that will drop in. I replaced the OE Chinese cheapie with a higher quality NAPA battery, but it didn't make much difference.

Heavier gauge cables might help a bit, especially if the negative cable attached directly to the starter mounting bolt.

Oddly, my tired 25hp Robin that ate a whole bunch of dust in the first year that I owned it has gotten better at cold starting in the last year. It should be dead, but it seems to be getting better.

 

[BobRip]

Heavier gauge cables might help a bit, especially if the negative cable attached directly to the starter mounting bolt.

.

My experience developing battery powered products shows that reducing losses in wires can make a big difference in operation. This is cheap and easy (I think) to do. I have not tried it though on a PT. A heavier wire tied directly to the starter bolt would be with trying.

 

[ponytug]

I agree. One of the first things that I did after getting my PT was to up the battery cable sizes, and add a central ground point on the engine, with extra ground wires to the front and to the tub itself. I also sanded the ground point on the engine for the best electrical connection. (In hindsight, I probably should have run one over to the ground screw on the the electrical interconnect, but that was before I had taken it apart.)

As always, YMMV...

All the best,

Peter

My experience developing battery powered products shows that reducing losses in wires can make a big difference in operation. This is cheap and easy (I think) to do. I have not tried it though on a PT. A heavier wire tied directly to the starter bolt would be with trying.

 

[BobRip]

I agree. One of the first things that I did after getting my PT was to up the battery cable sizes, and add a central ground point on the engine, with extra ground wires to the front and to the tub itself. I also sanded the ground point on the engine for the best electrical connection. (In hindsight, I probably should have run one over to the ground screw on the the electrical interconnect, but that was before I had taken it apart.)

As always, YMMV...

All the best,

Peter

How does your machine start below 50 deg and 40?