Cost for crank bearing replacement 2 stroke outboard and recommendation in Devon/Somerset?

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Any ideas on typical cost for a 10hp twin cylinder 2 stroke to have crank and while in there little end bearings replaced?

If anyone can recommend a place to have it done as well that would be great. I'm in Torquay so that area ideally but travel to Bristol weekly.
 
What make of outboard? If the centre bearing isn't gritty, I wouldn't replace that one as it requires the crank to be split whereas the end bearings just pull off. If the crank does need splitting, try motor cycle engine repairer if local outboard dealers can't do it. No idea on cost.
 
Its the tohatsu 9.8, the rarer light weight one which is why i'm thinking its worth doing. Its giving a pronounced ticking that rises with the revs, very consistently with them. I took off the starting assembly so knew its not that. Same whether in gear or out. Had someone look at it today, checked compression which is fine and he's sure its not piston slap, pretty sure bearings but with these you can't just take the bore off like a motorbike to try the little ends first, the whole case has to come apart so its gone beyond what i'm happy with doing myself, and might as well change both ends of bearings. Guy I spoke to seemed good but would be nice to have a second quote as its not a small amount of money.

Its a bit of a puzzle as its hardly been used. Only thing I can think of is I twice ran it hard where the boat was too heavy to plane and I was impatient one time and rushing for a tide window the other, both a couple of hours running and it was on that second one where i noticed the sound coming on. Is that how to kill the bearings? Pushing a fat bow wave where the engine is unable to rev freely, so more power demand with lower revs = less lubrication?
 
Well worth doing, they're a sought after engine. I stripped and rebuilt a T9.8 a couple of years ago, very easy to work on, except for one sheared head bolt which I Helicoiled. It also ticked but main reason for stripping was because it had overheated due to blocked thermostat and when I had the head off, decided to strip it. Found the drive shaft seals had failed and the bottom crank bearing was knackered with salt water ingress so just replaced that and the top bearing.
Found very small indentations in a piston and the head and it appears the bottom bearing was breaking up and a bit had been sucked up.
 
Is there anything in the job that requires specialist equipment like a press? I should have a go if not. Guy I spoke to seemed like the sort that wouldn't mind doing a part of a job if needed. Wheres the best place to source the parts?

Interesting about your cause of bearing failure. Do you know where the water got in?
 
Athomson said:
Is there anything in the job that requires specialist equipment like a press? I should have a go if not. Guy I spoke to seemed like the sort that wouldn't mind doing a part of a job if needed. Wheres the best place to source the parts?

Interesting about your cause of bearing failure. Do you know where the water got in?
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I don't have a press these days so improvised, only had to make a simple puller from flat bar and a couple of bolts to remove the flywheel.

Drive shaft seals had failed, they are in a housing and I ended up replacing the housing (which shattered) as well as the seals. See parts - 16, 18 & 19 on page 1 here - Tohatsu 6/8/9.8 PARTS LIST (motolodka.ru)

All parts available via any Tohatsu dealer, Ski Marine posted to me - SKI-MARINE (BOURNEMOUTH) they were one of the ones recommended by Tohatsu UK.

Certainly a worthwhile cost effective DIY job but, with labour charges these days, questionable if worth paying for dealer repair.
 
Even the parts seem expensive TBH, £40 for a head gasket? So add in labour and yes its really getting expensive. But I watched this
and am wondering if the head even needs to come off to do the rebuild. Looks like not unless I'm concerned about the thermostat.

If thats the case its a better design than needing to remove head and bore with their gaskets to replace when you can just open the low pressure area crank case with no expensive gasket needed and pull it out from there. The fact the power head is just 6 bolts to remove makes it all look a doddle. Feeling like doing it myself anyway now thanks for the encouragement.
 
Is there a bearing in the centre of the crank, between the 2 x webs? If so, the whole crankshaft will have to be separated, which is quite involved. The difficulty is getting the 2 x webs back into EXACTLY the same spot, otherwise the engine will always be out of balance and the timing between both cylinders will be out. Many years ago I had a Kawasaki JS550 jet ski (twin cylinder 2 stroke) that had a noisy centre bearing. there was only 1 company willing to separate the crank, based in Essex. Even then, I think I paid about £100 to have the work done? See if you can find someone who specialises in 2 cylinder 2 stroke motorcycle engines in your area who is set up to do the job.
 
mickywillis said:
Is there a bearing in the centre of the crank, between the 2 x webs? If so, the whole crankshaft will have to be separated, which is quite involved. The difficulty is getting the 2 x webs back into EXACTLY the same spot, otherwise the engine will always be out of balance and the timing between both cylinders will be out. Many years ago I had a Kawasaki JS550 jet ski (twin cylinder 2 stroke) that had a noisy centre bearing. there was only 1 company willing to separate the crank, based in Essex. Even then, I think I paid about £100 to have the work done? See if you can find someone who specialises in 2 cylinder 2 stroke motorcycle engines in your area who is set up to do the job.
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I was quoted a days labour for the whole job (8x£50/hour) which could of course increase, so paying just £100 for that part isn't too bad sounding.
 
Athomson said:
so you left the middle one? The outers were easy on with freezer for crank and heating the bearing?
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Yes, left the centre bearing, it was nice and smooth as was the top one but replaced that anyway as it was easy to do. No freezing or heating, just basic tools and a puller to get bearings off and I used 3/4" drive socket on one end and an old box spanner on the other to drift the new bearings on with large hammer :)

Your labour quote of 8 hours @ £50 will presumably be + VAT and as well as extra hours, you need to add a couple of hundred for gaskets and seals. If you have to pay to split the crank if big ends or centre bearing need replacing that's all on top, as are pistons/rings etc if needed.

Whether it's economically viable to have all the work done professionally is for you to judge, a new engine (if you can persuade a dealer you're a commercial user) is around £1,800 and a replacement used one will be pretty old and maybe needing attention before long. Many of those 8 hours you've been quoted are for stripping and reassembly both of which are simple enough to DIY so I suggest you dismantle the engine yourself, find what's wrong and then decide whether it's worth the cost if you need to pay someone.
 
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Graham376 said:
Yes, left the centre bearing, it was nice and smooth as was the top one but replaced that anyway as it was easy to do. No freezing or heating, just basic tools and a puller to get bearings off and I used 3/4" drive socket on one end and an old box spanner on the other to drift the new bearings on with large hammer :)

Your labour quote of 8 hours @ £40 will presumably be + VAT and as well as extra hours, you need to add a couple of hundred for gaskets and seals. If you have to pay to split the crank if big ends or centre bearing need replacing that's all on top, as are pistons/rings etc if needed.

Whether it's economically viable to have all the work done professionally is for you to judge, a new engine (if you can persuade a dealer you're a commercial user) is around £1,800 and a replacement used one will be pretty old and maybe needing attention before long. Many of those 8 hours you've been quoted are for stripping and reassembly both of which are simple enough to DIY so I suggest you dismantle the engine yourself, find what's wrong and then decide whether it's worth the cost if you need to pay someone.
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Thats a good plan but doubt it will be until after summer. I can live without it until then though. Strange thing about this engine, its from 2006 but very clearly had not been used more than a handful of times. It sounded fine when I bought it but developed this pretty quickly. I wonder if it might be same problem as yours, age does cause damage as well as use doesn't it, maybe a seal has gone inside. I replaced all the accessible rubber parts, impellor and water pump seals, fuel hoses, on the assumption they might have deteriorated over time. When I take it apart if it seems worthwhile saving I'll bear that in mind and replace everything perishable.
 
Athomson said:
I was quoted a days labour for the whole job (8x£50/hour) which could of course increase, so paying just £100 for that part isn't too bad sounding.
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The £100 was just for literally separating the crank, fitting bearing and re-fitting. I took the crankshaft and bearing to the company one week and collected it the next. This was probably about 20 years ago as well!
 
mickywillis said:
This was probably about 20 years ago as well!
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That makes the 400 todays pounds for everything seem highly unlikely then. He said he hasn't done one for years as people just throw them away now. But your idea of finding someone set up to do it is sound. This will be a slow job where I don't order anything until I'm sure it needs replacing and hope the middle one doesn't.

That said how hard can it be to line those up? Scribe on them before splitting and line up the marks before pressing? What am i missing?
 
Athomson said:
That makes the 400 todays pounds for everything seem highly unlikely then. He said he hasn't done one for years as people just throw them away now. But your idea of finding someone set up to do it is sound. This will be a slow job where I don't order anything until I'm sure it needs replacing and hope the middle one doesn't.

That said how hard can it be to line those up? Scribe on them before splitting and line up the marks before pressing? What am i missing?
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I think that some sort of jig is used to get the accuracy for alignment? Bear in mind that the press will have to push either on the shaft or the crank webs, it could easily go out of alignment if not correctly supported?
 
mickywillis said:
I think that some sort of jig is used to get the accuracy for alignment? Bear in mind that the press will have to push either on the shaft or the crank webs, it could easily go out of alignment if not correctly supported?
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I watched a few videos on youtube and its beyond what I want to get into but this seems promising kpmotosolutions
 
Just an outside thought, but why not pull the head and see if there is anything that causes the ticking? That only costs a head gasket. I found one for my Suzuki for about £10 off the wezb.
On durability, my 1980 Yam aircooled 3.5 has only stopped because of ingnition. But not sure which bit! Coil tests OK. So points etc.
 
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