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Mark Taylor
Member
Username: dart
Post Number: 11
Registered: 02-2006
| | Posted on Tuesday, August 15, 2006 - 04:25 pm: | 
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My R3M won't start - but the spark is very good, the fuel recent and the plug gets wet from the fuel after turning her over a few times. So there's spark and suction from the carb (stuart) into the chamber. And compression seems ok - good suck noises, and quickly tired arm from turning her over. Any ideas of what I am doing wrong? |
Peter Ogborne
Senior Member
Username: peterogborne
Post Number: 163
Registered: 09-2002
| | Posted on Wednesday, August 16, 2006 - 06:52 am: |
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Mark....it could be that your mixture is too rich.Is the air valve screwed right in ? If that is the case screw it out about a quarter of an inch.
Also try a new spark plug ,it wont fire if it is wet.
Check the float level as well. |
Mark Taylor
Member
Username: dart
Post Number: 12
Registered: 02-2006
| | Posted on Wednesday, August 16, 2006 - 08:40 am: |
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Hi Peter,
Thanks for that - I have tried the air valve in various positions but to no avail. Presumably the air valve acts as the choke? Is it a 1/4" to start, and then weaken the mixture, or how do you choke it? Also is it very susceptible to flooding? It's a new spark plug, and gap is right - like I say, lovely blue spark when you turn the engine. Float level might be suspect. But I am baffled - I have always run seagulls, and they always start whatever - they just run roughly if the mixture is wrong. Is the Stuart much more sensitive? Would the timing be another thing to look at? Are Stuarts normally easy to start? I was worried that being an old engine the crankcase bearings might be worn, but presumably even then, unless the engine was worn to bits, it would actually start (seagulls always do!)
Thanks
Mark |
Peter Ogborne
Senior Member
Username: peterogborne
Post Number: 164
Registered: 09-2002
| | Posted on Wednesday, August 16, 2006 - 07:28 pm: |
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Mark....there is no choke on these engines ,the air valve ,ie the brass perforated air intake is set and left in the best position for running. As I said this is usualy about a quarter inch screwed out.
The float level is very immportant. Firstly take the top of the float chamber [unscrews] .Turn the fuel on. If the level comes up to the top allmost two things could be wrong.
The valve is leaking ....on the top of the float there is a brass clip ,squeeze it in and you can pull the float off. You will see a groove in the needle valve ,this locates the float in the correct position...this is one thing to check.
Going back to the needle valve ...this works by being pulled up by the float. You can check if it is seating by just pulling it up with the fuel turned on. If it leaks then you will have to lap it in with some fine abrasive [Brasso].
The bearings would have to be very bad ,allmost in a collaped state to effect the crankcase sealing, the oil seals could be the trouble but you would have to strip the engine to replace these ...if you do use the neoprene ones.
If as you say the plug is very wet then it sounds like float level or leaking float chamber needle valve not seating.
I am taking a couple of my Stuart Turner engines to a show this weekend, a R3M and a P5. |
Mark Taylor
Member
Username: dart
Post Number: 13
Registered: 02-2006
| | Posted on Thursday, August 17, 2006 - 05:08 am: |
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Peter,
Thanks for that. I have ordered a new needle from Fairways, as I think that may be the problem. I did actually get it to fire last night - so that's a good sign! One I have had a go at the carb with a new filter and needle, fingers crossed it will go! Next job wil be to get the right boat for it go in! |
Fearghal Canning
Visitor
| | Posted on Monday, August 21, 2006 - 06:29 pm: |
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Mark, I have a P5 that i recently overhauled. Prior to the overhaul it was very hard to start. What i have is a piece of steel pipe with two slots cut to fit over the pins on the starting shaft,the end was sealed and a heavy allen shaped bar welded on to the end. This all fits very neatly into a cordless drill. 21st century starter for a P5. Its great when the same battery lasts for a full week, only needing to turn the engine over 4 or 5 times or so before it kicks into life. So much easier than swinging the handle. |
Malcolm Russell Ward
Member
Username: russell
Post Number: 11
Registered: 08-2003
| | Posted on Saturday, August 26, 2006 - 05:03 pm: |
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Really though, if they are set up OK (and I mean OK!) they start easily enough. You must have the obvious: good spark, good fuel with right oil concentration in the fuel (I use straight 30 grade) and compression. My little darling starts first wind and will mostly start flicking the flywheel -but not in front of witnesses. You do not need winding revs and anyway, the impulse mag doesn't impulse if it is wound fast. It is a special flick of the wrist which takes time to develop. I found that the timing is quite critical -mine is an impulse mag and these are quirky (follow the instructions). I had the timing out a tad and there was no life at all not even a kick. Once I got it right off she went as always.
Original ci piston and all.
If they weren't good when sold, they wouldn't have made so many. It was just when they needed a bit of tlc and didn't get it that they got grumpy. |
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