Rapier wrote:Thanks both, am happy to be taught as am an overly enthusiastic amateur with not much mechanical knowledge
Me too.
I suspect your skills would exceed mine by a fair bit
If the wire was bad,I think she would idle poorly as well. If you had it on the water you could hang a timing light on the bottom plug ,it would show if there was intermittent spark.Boat would be moving,which would be fun,if you're hanging over the transom.
no matter how bad it is,it can always get worse,I'm an optimist
Hung over it on Sat...opened the throttle manually and the bow came up so high I thought the boat would fold over me .. and I'd disconnected the kill cord - it was too short to reach where I was. Less said about it the better...
Following a slow day at Chertsey, we think this is the culprit and the magneto plate was not hitting it's stop at full throttle. I did wonder why it was such an odd shape, but it's been forced - I pulled the 40hp Johnson flywheel to check all other settings, then posted pics to the pros at JEGOs, as I was still stumped. Hoping to test it at soon, just to make sure and then run it up and down So'ton Water before Cardiff to make sure is reliable.
That bent link certainly isn't helping things. I just had a look at my Big Twin and wound the throttle fully open. Mine doesn't quite hit the stop, probably about 1/8 inch short, but may get there due to vibration when running. The plug leads seem to be offering resistance not surprising as they get quite contorted. I can't get a decent angle to get you a pic of what the link should look like as mine has the pull start and flywheel fitted. But my link has neat 90 deg bends. Yours will probably re-shape with careful use of pliers.
Edit
Thinking further about this, the only thing affected would be the control rod setting so you needn't be too accurate with the straightening so long as you set up the collar in the right place as pic
I sent this scan to RNB and Moonman sometime ago when they were having similar troubles, I had been thinking that you all have the same fault, perhaps this is not the case.
Thanks for this - I had the same concerns with plug leads by the way, even if the 5mm cut-back of leads took little slack out. This is the full post on JEGOs. I think I am at Bruce's final post point already, which means I'm there in terms of being ready to test. Is that the '71 manual?
p.s is possible a gathering is needed, or everyone to post pics on picasa. It really was the only way to work it out - I'd discussed with you and another willing expert, but just couldn't narrow it down until a kind gentleman came out with me at Chertsey and listened..
Just read the jegos thread very comprehensive answers As you say you have done it all to the end so all should be well.
Just a thought, did you get brutal with the plug leads and bend them about with a meter connected? To make sure they are sound.
My 71 Big twin ran very well flat out even if the full stop wasn't being reached.
The scan is from my 72 manual I have a 69 Johnson manual, the words are exactly the same for the setup with only detail differences in the photos regarding timing marks.
They're a good reference point, but I try not to ask questions unless am really stuck - you can imagine how many times they tell people to buy manuals...
I cut back the HT leads at the coil end by few mm, even with all the jiggling around get good and consistent readings. I'll possibly make up new ones as they do seem a bit 'tight' now and I noticed with the Johnson the bracket comes off one the top cylinder head bolts, rather than down the left side on the Ski Twin. I found the fuel pump I was supplied an odd fit too, there must have been two types, worthwhile bearing in mind
I am down your way on Sunday for the boat jumble so could chat with you there, maybe even lug my big twin into the car for comparison, although I may be accompanied by a small boy with an even smaller attention span. I wouldn't be too convinced by the position of the bracket on the Johnson it has possibly been moved by a previous owner after head gasket job.
Interesting fuel pump detail I had thought they would all be the same.
Will catch up at the jumble - promised to bring mine if it helped her Mum. Is a schlep to lug those around, so don't worry - at some stage this week I'll do a test run even if it means tying it to the piles at high tide and using the test prop. If it's all good, then 4 hours running on the Thames run will follow next week - it's been 28 years since it's last launch there.
Spent a very pleasant day on the Hamble River yesterday. Great neap tide and put up with 'the wrong trousers' jibes in my waders The slipway has no pontoon so one has to launch, run the boat to the public pontoon, find a spot to moor up, go back to the trailer, park 8 minutes walk away and trudge back to the pontoon. Sadly the Ski Twin proved somewhat unwell again.
Hung over it on Sat...opened the throttle manually and the bow came up so high I thought the boat would fold over me .. and I'd disconnected the kill cord - it was too short to reach where I was. Less said about it the better...
soon, just to make sure and then run it up and down So'ton Water before Cardiff to make sure is reliable.
As you say you have done it all to the end so all should be well.