Thundercat built thread!

[lukewhiting]

Been a while since the last update and had a few things happen since!

Managed to flip it the other week which was a first for me! Luckily out with another boat so all was well.

Stripped the engine down and cleaned it out and did a few small mods whilst I was at it.

Cut the ring gear off the flywheel and removed the lighting coils.



Took it out for its first test light night in some perfect conditions; flat calm in the bay with a nice swell out of the bay and some good surf in one part of the bay.

Unfortunately after about an hour the engine suddenly ran lumpy, sounded extremely rattly and stalled.
Would not start again and after every effort to get it running I had to call out the RNLI for a tow!

The guys were fantastic and I was back safe in no time! Big thanks to them!


Did a compression test today and all seemed fine, fuel was getting to the cylinders aswell as a spark so couldn't see why it wasn't firing.

So took the pull start cover off and flywheel to find the woodruff key had sheared causing the flywheel to spin on the shaft; thus loosing the timing and the cause of the rattle!

Luckily no major damage just £2.70 for a new key!

[lukewhiting]

[Roflhat]

That's an interesting one... Could be the case that the ring gear reinforces the hub of the flywheel. When I cut mine the ring gear sprang open, so it might be that it makes the hub sit tighter on the end of the crank if you see what I mean

[lukewhiting]

Originally Posted by Roflhat

That's an interesting one... Could be the case that the ring gear reinforces the hub of the flywheel. When I cut mine the ring gear sprang open, so it might be that it makes the hub sit tighter on the end of the crank if you see what I mean

I think what it was more my fault haha

I tightened the flywheel down with a breaker bar but forgot to torque it up before I used it.

Think it must of come loose enough on the taper that the vibrations sheared the key

[watersidemat]

How much did you have to strip it down after flipping to wash it through. Flipping mine is a big worry of mine not because of the idea of going upside down just the heartache of starting again on the engine after all the hours I've spent on it to get it going! And also have you put in the steering damper you mentioned in earlier posts? It's something I need to get round to doing on mine but have no idea how where or what to fit.

[lukewhiting]

Originally Posted by watersidemat

How much did you have to strip it down after flipping to wash it through. Flipping mine is a big worry of mine not because of the idea of going upside down just the heartache of starting again on the engine after all the hours I've spent on it to get it going! And also have you put in the steering damper you mentioned in earlier posts? It's something I need to get round to doing on mine but have no idea how where or what to fit.

Didn't take much to be honest.

Removed the plugs and filled the cyclinders with wd40 and cranked it over until no more water sprayed out.

hosed it off with fresh water then began to remove everything (coils, cdi unit, flywheel, carbs, all fuel filters and lines, kill switch) until it was basically just the power head and cleaned it up with wd40.

Rebuild the carbs and blew out all the air lines with a compressor.
Dried out all the electrics, cleaned connections etc
New spark plugs.

Rebuild it all and she started on the third pull!

Didn't use fresh fuel as my tank was sealed when I flipped it but am running it on a rich oil mixture for now.

Took me about 4 hours from start to finish?



Also will be getting the steering damper in the next week or so. Try asking the racing guys if they have spares

[Roflhat]

Should just need to pull the plugs, drain the carbs, pull it over to remove the water then plugs back in and get it running. Leave it running for a good while to flush out the system. We had to do it to a mariner 30 which was at the bottom of the sea for about 20 minutes, had it going again up at the shed within an hour, still runs well

[lukewhiting]

Picked up some old classic mini steels for a bargain to put on the trailer.

Currently rubbing them down for a respray and need to get some new arches for the trailer but should be better than the old 8" wheels!