Lister ST2 Engine advice

[vindyboy]

Hello All,

 

New to the forum and this is also my first post. If I am in the wrong topic area please let me know.

 

My brother, friend and myself have just bought a narrow boat project. She has a Lister ST 2 air cooled engine.

Engine when finally started had a loud diesel type knock and was not firing from the front cylinder.

 

Head has been removed to find a bolt embedded into the piston and of course damaged a valve. I have not seen it yet.

Question and advice from Lister owners, is it okay to fit a new piston and valves with the engine in situation. I think the answer is yes but would like to double check. I realise I need to check rods to see if bent, hopefully look myself this weekend coming. I have found another engine which is supposed to have no issues and to be fair the seller said he would demonstrate it running. Just feel it might be easier and take less time to replace the parts .

I have added some pictures of my engine already fitted.

Any advice would be much appreciated.

Thank you.

[Boater Sam]

Unlikely to have bent the rod unless it was a big bolt. Check push rod on damaged valve for bend.

Find where the bolt came from, there could be another just waiting to drop in.......................

If the piston is not holed, it could well still be OK.

 

Engine is tough with a capital T

Edited October 9, 2018 by Boater Sam

[vindyboy]

Quote

 

Thank you very much for your reply and advice.

Will be at the boat this weekend so I can have a proper look. Very much appreciated.

 

 

[zenataomm]

How the merry dickens did a bolt get in the cylinder? 

It sounds like sabotage, or did someone drop a small one down the inlet with the air intake off?  It would have to be a small one as the valves when open don't give much of a gap.

 

I don't see how the piston could possibly still be serviceable after that, I'd also worry about the cylinder head.  The bump clearance is likely to be as tiny as three thou. 

I'd say your worse case scenario could be …..

Gouged piston

Cracked Head

Bent/smashed valve

Bent valve push rod

Bent con road

 

The last one you'll only know when you come to reassemble and check the bump clearance with a lump of solder.  If you can't get the clearance down to the dictated clearance then you're likely to have a bent con rod.  Sometimes you can't see it unless you have two next to each other to compare. However if you don't have the correct clearance you'll have a weak cylinder through not sufficient compression.

[vindyboy]

 How the merry dickens indeed, I really do not know.

 

I do not think sabotage.

The last owner owned the boat for 3 years, it was gutted inside for a total refit and has been on its moorings ever since.

The previous owner was a friend who was divorced and was going to live on it however did not, whilst he owned the boat the back end sank due to very bad moorings. It was lifted by the marina owner. I suspect because of this maybe the manifold and or air cleaner and perhaps it got in that way.

 

I have not seen it yet because the resident mechanic removed the head for me and telephoned me to say what he had found. I will be there this weekend so will see for myself.

 

He suggested replacing the engine, I would like to replace the parts and leave the engine in.

 

I will post some pictures over the weekend.

 

Thank you so much for your  advice and comments.

[RLWP]

I disagree. You are very, very likely to have bent a rod. The correct clearance between the head and piston is about 0.75mm - no room for a bolt

 

Richard

[Boater Sam]

BMC engines have a habit of throwing the combustion top hats in bits into the pistons.

The metal chunks, around 3 or 4 mm, embed in the ally pistons. If you knock them out, they run fine providing the piston edges are not crushed to grab the top ring.

When the foreign object gets trapped between the piston and the valve or head, the con rod is very near top dead center, straight up off the crank pin and resists bending end on. The piston is soft, the valve and push rod will bend, absorbing a lot of the shock. I used to get diesel engines in with cam belts gone at high speeds on the motorways, bent valves and overhead camshafts smashed, knocked right through the bearing caps, sheared off studs, the works, but seldom a bent rod or crank.

Edited October 9, 2018 by Boater Sam
added more

[RLWP]

I must take pictures of my bent Lister rod collection

[vindyboy]

1 hour ago, RLWP said:

I disagree. You are very, very likely to have bent a rod. The correct clearance between the head and piston is about 0.75mm - no room for a bolt

 

Richard

Hi,

 

As I am new to lister engines.

 

If you were in my position would you replace the engine or repair it.

If I could replace the damaged parts including the rod if needed can this be done with the engine it situ, or does it have to be removed from the boat?.

 

Jeff.

[Boater Sam]

 

1 hour ago, RLWP said:

I must take pictures of my bent Lister rod collection

Fair comment, I've not had many Listers on the rack. Most of my diesels were high speed road engines and pumps.

I wonder if sometimes a slightly bent rod is missed and the motor still runs OK, depends which way it bends I suppose.

Its amazing what an engine will run with.  We had a Hillman Hunter driven back to the UK from Saudi once that had a hardwood piston fitted in Morocco. Beautiful bit of machining, not sure what wood, no rings but it ran.

Edited October 9, 2018 by Boater Sam
Duplicated

[bizzard]

11 minutes ago, vindyboy said:

Hi,

 

As I am new to lister engines.

 

If you were in my position would you replace the engine or repair it.

If I could replace the damaged parts including the rod if needed can this be done with the engine it situ, or does it have to be removed from the boat?.

 

Jeff.

There is a lower crankcase door on those engines which will give access to the conrods bigends to undo them.

[vindyboy]

4 minutes ago, bizzard said:

There is a lower crankcase door on those engines which will give access to the conrods bigends to undo them.

Great, thank you.

 

[bizzard]

3 minutes ago, vindyboy said:

Great, thank you.

 

Its the lower door beneath the cooling hot air outlet ducts. Port side.

[vindyboy]

Quote

 

Okay, great. Thank you again.

[zenataomm]

1 hour ago, Boater Sam said:

 

………..  We had a Hillman Hunter driven back to the UK from Saudi once that had a hardwood piston fitted in Morocco. Beautiful bit of machining, not sure what wood, no rings but it ran.

Amazing, you'd think it wooden go. 

[RLWP]

9 hours ago, bizzard said:

There is a lower crankcase door on those engines which will give access to the conrods bigends to undo them.

Exactly. There are quite a lot of jobs you can do on a Lister in a boat. You may have to hang upside down for a while to get to the big end nuts though

 

Richard

[vindyboy]

Might have to get my friend to do any hanging upside down, I think he is part bat.

Great to know most work can be carried out in the boat.

Jeff.

[RLWP]

Before you do pull the rods, do a bump clearance check as described in the book. If that comes out OK, your rod is fine

 

If you have to take out the head gasket to get the right clearance, the rod is bent

 

Richard

[vindyboy]

Great advice. Thank you very much.

 

I will hopefully be able to do this weekend.

 

Thank you again

[Tony Brooks]

1 hour ago, RLWP said:

Before you do pull the rods, do a bump clearance check as described in the book. If that comes out OK, your rod is fine

 

If you have to take out the head gasket to get the right clearance, the rod is bent

 

Richard

Comment on this thought Richard or Biz/Sam. If the bump clearance is only a very small amount over size indicating a possible bent rod and assuming the ST is like the SLs with shimmed head gaskets I suspect it will still run fine if you can get the bump clearance by removing/changing shims.

[RLWP]

14 minutes ago, Tony Brooks said:

Comment on this thought Richard or Biz/Sam. If the bump clearance is only a very small amount over size indicating a possible bent rod and assuming the ST is like the SLs with shimmed head gaskets I suspect it will still run fine if you can get the bump clearance by removing/changing shims.

Yes - as long as you can get away with taking out shims, not the head gasket

[Stilllearning]

14 hours ago, vindyboy said:

Hi,

 

As I am new to lister engines.

 

If you were in my position would you replace the engine or repair it.

If I could replace the damaged parts including the rod if needed can this be done with the engine it situ, or does it have to be removed from the boat?.

 

Jeff.

Taking both cylinder heads off, and measuring the height both pistons come to in their bores, may well tell you right away if a conrod is bent.

Equally, opening up the side plates and looking at the rods may help.

If nothing else, you will get to know much more about the engine while you are doing it all. They are very simple, proper old-fashioned diesels, and easy to work on. Parts are available, and RLWP who has already replied to you, is an expert on them, and can supply any parts needed.

[vindyboy]

On ‎10‎/‎10‎/‎2018 at 11:01, RLWP said:

Yes - as long as you can get away with taking out shims, not the head gasket

Hi All.

Just an update and pictures from yesterdays boat visit.

 

It is a nut and not a bolt as first told embedded into piston.

We are of the opinion that the nut came from inside the air filter housing. According to Nick the marinas resident mechanic that the original nut should have been a locking one. Looks like it was replaced with a non locking one which through vibration came undone and made its way in to the cylinder.

Bump looks okay according to the manual.

Valve and guide is damaged, other than that the head looks okay.

 

We intend to replace the piston, clean up the head, fit new guide and valve.

I believe the piston is standard. Piston number is 201-82045/6/12.

 

I have seen a piston £57.60, valve £10.00, valve guide £6.50. 

Also need gasket for the side crank door. 

 

I did post this yesterday and had some comments on my jeep that I added by mistake.

I have added some pictures of the damage and because of the interest added the picture of my Willys.

 

Jeff.

[Alan de Enfield]

I bet your insurance is about due on the Jeep - bet you need a valuation ?

 

(Nice)

[Boater Sam]

I'd clean that piston up and run it. The nut has stayed put and not damaged the edge of the piston which would trap the top ring. Run a lot worse than that in the past and had no trouble.