Starter won't turn the engine over

Wow.. that's pretty intens.

 

Looking for updates on how the engine is coming along. If you did all the checks from the above posts you should have some news for us.

 

Thanks all. Lots to catch up on, but have been tackling other projects today. I'll review and act based on comments, and report back on progress this week.

 

Sorry, just read comments. So we're assuming possibly fuel leaked into a cylinder, and perhaps into the crankcase, one of those preventing turnover? Drain the oil and check for separation, pull the plugs and look for pooled liquid in the cylinders?

 

If you take the plugs out disconnect your battery first and turn the engine over with a spanner on the end of the crankshaft slowly preferably outside your garage in case a cylinder is full of fuel.

 

Gotcha, thanks. I worked on a LeMons team for a few years, and we did set an engine bay on fire placing the plug against the block to check for spark without disconnecting the injector. We had a fire extinguisher and all was fine, but I've been sure to have one on hand since. Appreciate the guidance on next steps, I'll check it out and report back.

 

Removed the plugs and drained the oil. Snapshot of oil: https://photos.app.goo.gl/QguC7xiHAT1w3ovB8 I see a hue of blue, not sure if that's a concern. Looking into the cylinders, no evidence of pooling fuel. Unable to rotate the crank with slight pressure on the crank.

 

back in post #8, is that on the crank marks? because the cam looks about one tooth off

 

Is it safe to rotate the crankshaft backwards/clockwise? If not, I don't think I can confirm. I believe I'll need to remove the head, check the valves, and realign/reposition everything.

 

With the oil out of the engine and no fuel in the cylinders it's got to be cam timing. If you turn the crank try and get all the pistons away from the cylinder head to be clear of the valves. Turn clockwise as it was locking when turned anticlockwise. Yes you need to check the head, valves etc.

 

Yes it is definitely out.

 

Does the oil smell of Petrol? If not petcock should be working properly.

 

Looking at the position of the T mark on your rotor piston two or three could be hitting one of the valves.

 

Cylinder 2 looks like it may be the cylinder of interest, though I can't tell too much peering through the spark plug hole and cam/piston positions. Winter has come in Chicago, so it'll be slow going for a while, but I'll remove the head and check the valves/pistons. While I'm in there, I'll do a thorough cleaning of the head and change the valve stem seals as well, something I should have done initially with this transplant.

 

Yes inlet valve no 2 is depressing the valve in the photograph. If you can turn the engine clockwise and get the T mark on the line on the plate held by the single screw that's 1 and 4 TDC mark. I think the dot on the camshaft will be nearer the head instead of near the triangular timing mark on the alloy caps when the T mark is at TDC.

 

Engine runs anticlockwise so the piston has come up and hit inlet valve No 2 by the looks of it.

 

Update: Took the head off and removed the valve assemblies for inspection. Didn't notice any damage, didn't even notice signs of impact (though I agree that is likely the cause of the problem). Reassembled, and noticed that while installing the chain sprockets on the camshafts and rotating a full cycle, the intake would fall a chain link or so behind the exhaust camshaft, even though they were lined up initially and the chain pretty tight. I'm guessing the chain was not taught enough, and I probably assumed the difference was 'close enough'. Didn't allow myself that clearance this time. Had to advance the intake camshaft a few degrees, to the point that they misaligned inversely (the intake camshaft was ahead of the exhaust camshaft). However after a full rotation, they aligned perfectly.

Bottled everything up, and it ran again, sounding much better than before. The carbs are clearly out of tune, but that's a better problem to have.. I'll be tackling that next. I also found a colortune, so I'll search for some guides, but would appreciate any links to good posts/articles/videos.

 

Are you going to rebuild the carburettors? Here is a how to bench sync them although a full rebuild would be better.

https://xjbikes.com/forums/threads/how-to-bench-synch-your-carbs.6366/

 

Thanks for the link. I'd recently rebuild the carbs (mileage-wise) and bench sync'd them, but I've bought supplies to liquid/vacuum tune them as well.

 

I'd like to close this thread. I've turned the engine over many, many times. A previous rattle sound has long subsided (since adjusting the cams to match the timing marks), and that alignment hasn't shifted. I think it's clear my cam alignment was off, and valve(s) were tapping on cylinders. I assume the engine stopped at a position where the starter couldn't turn the engine over due to the interference. For what it's worth, I disassembled and inspected all the valves, and saw no damage (nor on the pistons). I've reassembled, assured the timing aligned after many revolutions, and the engine is running much healthier. Not as healthy as I like, but I believe that's another issue, and I'll search/create another thread that fits the current situation. Thanks all!