JS3M cold start

[Nds123]

Forgive me asking all of you this question , And this is because am new to it all.

But my question is what is the best way to start a cold JS3M engine? If I don't ask I will never know from all you experts .

The other question is I need to change the cooling with anti freeze etc. what is the best method for meto do this.

Thank you all for your help.

[onionbargee]

you mean JP3M ?

[Lockie Junior]

No, the OP does mean a Lister JS3M. Bit more power than a JP3M, plus its one of the best sounding boats on the river.

 

Regards,

Lockie.

[frangar]

you mean JP3M ?

Not necessarily! The JS was one of the last variants of the JP range...I think it has pressure fed top end lubrication and no compression changeover valves....it's also rated for a higher rpm...possibly 1500 rpm instead of 1200 rpm

 

As for starting do you have hand or electric start?.....I take it that it doesn't start that easily from cold?

 

Changing the antifreeze is just a matter of draining and or pumping the old stuff out and replacing with a fresh mix....use the blue stuff though not the 5 year pink stuff.

 

Cheers

 

Gareth

[RLWP]

Changing the antifreeze is just a matter of draining and or pumping the old stuff out and replacing with a fresh mix....use the blue stuff though not the 5 year pink stuff.

 

Cheers

 

Gareth

 

Having made sure you don't have a raw water system...

 

Richard

[frangar]

Having made sure you don't have a raw water system...

 

Richard

Indeed....mind you if it does then it might be tricky to find where to top the system up.....

 

Cheers

 

Gareth

[Timleech]

Not necessarily! The JS was one of the last variants of the JP range...I think it has pressure fed top end lubrication and no compression changeover valves....it's also rated for a higher rpm...possibly 1500 rpm instead of 1200 rpm

 

As for starting do you have hand or electric start?.....I take it that it doesn't start that easily from cold?

 

Changing the antifreeze is just a matter of draining and or pumping the old stuff out and replacing with a fresh mix....use the blue stuff though not the 5 year pink stuff.

 

Cheers

 

Gareth

 

May be wrong, but I think they went back to dual compression for the JS, having abandoned it for the JK.

 

Tim

[Nds123]

Not necessarily! The JS was one of the last variants of the JP range...I think it has pressure fed top end lubrication and no compression changeover valves....it's also rated for a higher rpm...possibly 1500 rpm instead of 1200 rpm

As for starting do you have hand or electric start?.....I take it that it doesn't start that easily from cold?

Changing the antifreeze is just a matter of draining and or pumping the old stuff out and replacing with a fresh mix....use the blue stuff though not the 5 year pink stuff.

Cheers

Gareth

[Nds123]

No it is a JS3M with a blackstone 1:1 gear box from a 1946 fishing boat 1500 revs gives me 45 hp

I to have electric start which is great ,however i have stated her when the engine is warm but it's very hard from cold.

That why I have ask if one day I had no power from batts Etc I would like to thing I could start her from cold.

 

I have a skin tank that holds the antifreeze and what's around the engine .

If I find out how to post photos on this site I will put photos on

[martyn 1]

 

May be wrong, but I think they went back to dual compression for the JS, having abandoned it for the JK.

 

Tim

The JP came first with duel compression 15:1 and 19:1 and 1200rpm max

 

The JS was the second development, still with duel compression but a higher top RPM of 1500rpm and the introduction of the change to an oil feed on the rocker shafts. These engines caused a lot of problems for Lister as running like this for long periods the cranks broke. JS's were also only ever made in 3 cylinder versions.

 

The JK was the last variant with fixed compression at 17:1 and the higher rpm of 1500rpm and a re-designed crank to be reliable at the higher rpm.

 

Back to the OP's question if you engine is hand start them follow as below, if electric start miss the bit about opening de-compressors. (you can miss some of the steps below when the ambient temp is warm or the engine has been running but i wont confuse matter with that at this time)

 

1. check oil / water levels

2. Ensure compression changeover valves are fully screwed in. (one on the side of each head, looks like a tap)

3. Lift the overload pawl and ensure injector pump rack moves to full fuel position.

4. open decompressors (only needed for hand start)

5. turn engine starting handle until up to a good speed and close decompressors one by one. (hit start button if electric start)

6. engine should be running.

As for changing your coolant with antifreeze depends on the system but drain the skin tank out, and drain down the engine via one of the two block drains located at either end of the block just above the three small side doors. then refill the system ensuring to open the valve on top of the exhaust silencer once first started to vent out any trapped air.

 

This is a JS3M. externally pretty much identical to a JP except for oil feed to the rockers oh and the makers plate says JS not JP..... oh and for the OP the block drain has a valve in it at one end on this engine and a brass blanking plug at the other

Edited April 7, 2014 by martyn 1

[frangar]

Well I was almost right!!!

 

Cheers for clearing that up Martyn. I would also check what oil it's running on...mine is much easier to hand start on SAE 20 rather than SAE 30.

 

Cheers

 

Gareth

Edited April 7, 2014 by frangar

[martyn 1]

No problem Gareth

 

Good point about the oil. To the OP if you intent to hand start it especially in cold winter conditions go for a SAE 20 but if you will be electric starting then SAE 30 is fine. Incidentally we use SAE30 but this is more because it is compatible for both the JP's and the various Gardner's we do. Saves stocking two oils and all our engines leave electric start anyway so no issue there.

[starman]

I'm puzzled about the use of the overload pawl for starting. My JP3 starts first push of the button without using it. Is there any advantage to be had in setting it all the same?

[frangar]

The overload pawl makes life easier when hand starting but if everything else is in good order then shouldn't make much difference on electric start.

 

Cheers

 

Gareth

[martyn 1]

I'm puzzled about the use of the overload pawl for starting. My JP3 starts first push of the button without using it. Is there any advantage to be had in setting it all the same?

Its more important that it is there when normal running than if its needed or not for cold starting. Basically if its very cold and the engine is reluctant to start, by lifting the overload pawl it allows the injector pump to move past maximum running fuel into its absolute max position which is the cold start aid. So if you engine start happily without it then all is good. normally a JP will electric start even when very cold without the pawl. The pawl will make it start a bit quicker if you JP is one that cranks a bit before starting which is easier on the batteries or your body if hand starting.

 

The important bit which most people seem to miss and we have had plenty of JP's through the workshop with the damage from it. Is that without it being fitted the pump can go past the max running fuel position (the overload pawl is the stop normally) and makes it possible to be overfueling the engine during normal running at high RPM or wide throttle openings and therefore you end up with smoke because of unburnt fuel and eventually cylinder problems and coking up of the exhaust ports if left unchecked.

Edited April 7, 2014 by martyn 1