Err, it August now and engine decisions..

Not quite sure where the year has gone. Weather has been bad and work busy so things got put on hold.
With a bit more time I started looking into the engine itself. For those who don’t know these are refereed to as ‘power heads’. That simply means the engine itself. I had a couple knocking about with damage, and the plan is to make something work on this project.

Some pics:

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Stripped of ancillaries, and crank case cover removed. You can see the intake reeds main bearings and conrod big ends.

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Crank and pistons removed. Quite interesting as unknown to me, there is damage to cyl 3. One of the ring lands has cracked. No bore damage, but some crown and ring land damage.

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The damaged piston. You can see that the rings are stuck in place too. Carbon does this mostly. The rings stick, then you start to loose compression, or they can jam get caught and snap etc..

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The ring land damage.

Everything else looks fine, the bearings are good, and no issues I can see with anything other than sticky rings and a bit of sand getting into the engine, causing I believe this ring failure. Corrosion in the water ways isn’t that bad either. Clearly hardy engines these.

Soo..

I decided to then pull apart the old I6 engine that died on my mate The one in fact that had that propelled us around the IOW with the SBR massive!! This was rather more um interesting lets say.

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Both engines in bits. So I’d always known that the first I6 engine we had, had issues with its bottom water seal. And TBH it should have been fixed as soon as I saw this. I did try to remove the power head (engine block) from the mid section but it was stuck solid. 30+ years of corrosion. It wasn’t going anywhere. In the end I had to sacrifice the mid section and cut through it with an angle grinder and finally managed to separate the engine from it.

Anyway on the bench I pulled the crank case cover of and woah. Now I know what happened, namely THIS:

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On the left is a bearing carrier, the bottom crank one, and two water seals (well they were once) on the right is the old lower crank bearing- what’s left of it. The rest is around my bench and has been eaten by the pistons.. which as it happens look like this:

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Number 6 ouch… water getting into this one has ruined the conrod big end crank bearing surface, con rod and gudgeon pin bearings. Then failure of parts/rings etc has killed the piston BADLY and the bores don’t look great either.

5 isnt looking so good either:
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Notice two stuck rings.

No6 bore:
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Loads of impact marks on the combustion chamber surface.

But at the other end no 1 2 3 4 are fine, and are a perfect fit for my other engine!

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So what will happen now is I shall clean everything on the new engine, get a set of new rings and start re-assembling the whole thing with all new seals! Keypart have rings in stock, and I have everything else so shouldn’t take too long really

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