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Lister Blackstone advice

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pfg:
Hi and thank you for letting me join the forum!

I have a Lister Blackstone ERSM6 currently under repair and would appreciate some advice. I do have the original instruction/parts manual, but it does leave rather many details out. If anyone have knowledge of these engines and could help me out here I would be very grateful.

As a background, I purchased the engine together with all auxillary equipment (heat exchangers, air tanks, oil tank etc) 'at the side' and have started to install it in a boat. I've got it preliminary lined up against the propeller shaft and am now disassembling and renovating to put things back again by spring-summer next year. All cylinder heads are off, next is pistons and liners. The engine has not been running for approx 30yrs, so I recon I have to replace the double o-rings at the bottom of the liners. Probably need to special order those to be manufactured. Then I plan to indicate crankshaft and level the bedplate accordingly, to finally tighten the 18 M24 bolts (12 for eng and 6 for gear). If everything goes well, I will start it up sometime late summer next year. 

First issue is suitable cylinder head gasket material to manufacture my own gaskets. The old ones are, after many yers of duty, roughly 3mm thick and really compact. Now, question is what new gasket material to what thickness to use to get acceptable compression rates to fill the gap for the up to 0.4mm protruding liner? Usually you want the gasket as thin as possible, but able to get acceptable compression rates over the whole surface. Yes, the max cylinder pressure is listed as 66 kg/cm2, which seems pretty moderate?

Then, if anyone knows any weak spots of this particular engine and have tips on how to correct them, it would be really helpful. Not nice to find internal oil pipes burst while at sea!

Best regards,
Peter

cobbadog:
Hi Peter and Welcome to the Forum.
What part of the world are you in so that members can direct you in the right way. Here Australia there are many places to supply gasket material even make them for you quite cheaply as many of the old engines already have been copied depending on the exact model. Sometimes a sample one may need to be supplied but I understand you would like to make your own. Someone will be along hopefully with the right thickness paper to buy. Some head gasket paper comes with metal in the middle for the heat. Are the originals just a paper gasket or not?
 If you say the old ones come in at around 3mm then you will need at least 4mm thick new. As for the "O" rings, a local bearing shop will be able to put as many on the counter top as needed. This is something that is readily available. By taking a liner with you they can measure the size of the groove to get the thickness right and then measure the diameter of the liner and again get that right. Discourage them from supplying metric size "O" rings as they should be Imperial.

38ac:
While there are certainly much more talented people around than I but personaly I would not undertake shop made head gaskets for that engine when there are means to have them correctly made. As Cobbadog said there are several places here in the states to have it done but I use John at Gaskets To Go. He is an American who lives in Tiawain. The work is forst rate, prices are very reasonable amd delivery is quick. Hint: have and extra set, made.  it costs little. 

mobile_bob:
+1 with John at gaskets to go!

his gaskets are absolutely state of the art

i had him provide me with head gaskets for my s-195 and he sent me a half dozen for about 7 bucks each, that was maybe 12 years ago?

they are of vastly superior construction, carbon/metallic with print o' seal around all the water ports, excellent gaskets

i say this based on the extreme use i put them through, running the engine at max load with a pressurized cooling system running between 205 and 214 degF, absolutely no leaks or weeping at all.

far superior to the oem gaskets, and i suspect a quantum leap over indian head gaskets.
at 7 bucks each i can't imagine even thinking of trying to make one unless it was a zombie apocalypse and i had nothing to replace one with.... even then it would be a tall order to get something that would work for any length of time.

bob g

pfg:
Hi again and thank you all for the replies!

Yes cobbadog, I realize that I should have told more on the background and my plans, my bad!

I reside in Gothenburg, at the west coast of Sweden. As it is a coastal city, we have some old ships and henche ship engines near by. Most of them are Swedish or at least Scandinavian, like NOHAB Polar, Skandia, Seffle or B&W Alpha. The Lister Blackstone is quite rare. I am a member of a non-profit association for historical commercial ships, i.e. over 12m. Mine is 25m and considered medium sized. It is privately owned and renovated by me, which is on the edge but only works since I refurbish old equipment and try to learn along the way. I've attached a photo of the boat in the floating dock this summer when I did a overhaul with sandblasting and repainting.

The head gaskets are roughly 44x35cm, as the attached picture. The one installed are simply hand made, which can be seen on the uneven shapes, and made from a single piece of dense gasket material. The protruding liner is also clearly visible. I asked my local gasket provider, rima.se, and they kind of recommended Flexitallic RGS3, which is a steel reinforced carbon gasket. However, since they did not have any experience in combustion engines, they could not tell for sure that it would work. After talking to the manufacturer, Flexitallic, I found they did not know either. Guess they are more into chemical/process industry. Thing is I would not want to blow out this gasket, and if I could learn something about proper head gaskets and their compression rates at the same time it would be even better.

My original plan was to provide my gasket provider with a drawing, like dwg, and have them machine out the shape from a suitable material. They have a large sized gasket CNC knife cutting machine. This will be rater expensive including all the several m2 of gasket material as I would want 12 pcs, double my inital demand for the 6 cyl engine. 38ac and mobile_bob, you both recommended Gaskets To Go, that is gasketstogo.com in Thailand, right? They look really professional and I will definately ask for a quotation, but I think the total, inc trp and import charges, will be hefty. Even so, you have a point in getting the professional stuff, and there is only half zombie apocalypse here for the moment!

As for the gasket thickness, the manual list a liner projection of 0.23-0.35mm, so let's say 0.3mm. As an example, let's go for the RGS3, which has a max compression rate of 50%, which will then occur around the liner. Using a 2mm gasket, we then get the head to block distance 0.5*2+0.3=1.3mm, which corresponds to 35% compression. A 3mm gasket gives 40%. etc. Is this a useful way to deal with gaskets to make sure they do not leak or am I way off? 

Regarding the o-rings, since the cylinder dia is 8"3/4, or 222mm, the rings are around 240mm, which is too large for my present provider. Bringing the liner is possible, but not feasable since it is not easy to carry along. I use cranes and fork lifts not to kill myself while handling things. I'll see if I can find another company for the o-rings.

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