Birthday boat

[IAN_IParticipant @ian_i]

Hi AJ..

Sorry to hear the trauma.. hope the time out helps to sort things, after the weekend and birthday…!

You might have found the answer to the problem..

Regards,

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Thanks Ian

Fortunately Sam has no Idea about his intended present, so I"ll say nothing, and take him to dinner instead. Once I'm over my sulks, I'll see what can be done with the engine. Christmas is coming….

[lnvisiblemanParticipant @lnvisibleman]

Have you thought about a HUGE brushless ?? Like this would do the job I reckon **LINK**

[Mark TommyParticipant @marktommy83416]

Hi Amy I've not been on the forum for a while but have been following your build. I'm sorry to hear about your engine issues it's a real shame as the boat is amazing

just a a few suggestions that may help – does the engine have crankcase compression? Just check the main crank seals as they may be leaking. Also as the engine ran fine before but now has no fuel on the plug and also fails to make any signs of life even with ether, look at the lower skirt of the piston as it may be damaged which would affect the transfer port timing.

Good luck and I hope you find the solution

[ashley needhamParticipant @ashleyneedham69188]

AmyJ. Oh dear dear dear. The very thing you had not bargained on…the engine. Probably the only item on the boat you could not make a new bit for.

Despite being a cheap Chinese engine, this will mean that millions will have been made and either spares or a replacement engine are likely to be found.

The issue is of course time and the fact that all the bits have been hand made to suit one particular application so no substitute can be easily fitted.

Is it likely to be the read? and if so, perhaps just for the birthday moment, the other read could be borrowed to demonstrate the efiiciacy of the present just once before effecting permanent repairs.

Invisbleman. I will print a picture of that motor and put it on my wall….ESC required….250A !!!!! 30-70V !!!

Outrageous! A thing of beauty (not the only thing obviously)

Ashley

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi Mike,

Yes that would do the job and then some! only problem is, I didn't pay that much even for my car!

Mark

Thanks for the good advice, When my compulsory sulking period is over I will look into your very sensible suggestions. It seems to me that neither fuel or air is getting into the chamber, so you may very well be right. It is also puffing out the carb, which also has me thinking reeds.

Hello Ashley

I will probably try the reeds off the generator, before I start taking the engine apart, just to see. I don't want Sam to know until every thing is permanently sorted. (I bought a 30cc weed eater engine today that runs well, $15, so that may be an option,.I know I didn't want a weed eater to start with, but it's better than a non running boat!)

Thanks for every ones input, all suggestions will be seriously considered!

[Bob Abell 2Participant @bobabell2]

Amy J…..Don't despair!

Don't really know what your reeds look like, but I once made a reed for a model plane engine, out of an Erasing Shield

It was Spring Steel about 5 thou thick and it worked well

You may be able to use Feeler Gauge material?

I would have thought that spares for reeds would be available….off the shelf?

Bob

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Good thinking Bob!

I shall start my autopsy next week, and let you all know what I find!

thanks again

Aj

[shipwrightParticipant @shipwright]

Amy,

Sorry to hear about problem with the engine. Had a look around the internet – one suggestion was fuel line filter. I assume that you have already checked that the fuel filter is clean. I assume that there is no risk that the copper screening is shorting out at the top of the plug (vibration might have changed the position of the screening). My gut instinct is that the problem is either electrical or fuel flow. Wouldn't a faulty valve give poor compression ? Also I would not expect a catastrophic valve failure – more likely is a gradual loss of efficiency and misfiring.

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Thanks Mike for your suggestions,

The plug sparks when held against the block, so it would be reasonable to assume it is sparking when screwed in? when I swapped the carb from the boat to the generator, the generator ran fine, so no carb issues. (the fuel is getting through to the carb just fine), which keeps bringing me back to the fuel/air mix not getting from the crankcase to the combustion chamber. So. has to be- reeds/ crankcase leaks (or cracks even?) /transfer port/ piston skirt.

I'm almost over my sulks, so my plan of attack next week will be to:

1) remove,inspect,swap the reed plate (I can do this with the engine in the boat)

2) If no joy, then the engine will come out and I will inspect the crank case for cracks, leaks etc, before pulling things apart!

3) I will consider replacing the engine as a last resort.

Sound sensible?

Thanks

[lnvisiblemanParticipant @lnvisibleman]

Sensible ?? Why change the habits of a lifetime ?

[Amy jane SeptemberParticipant @amyjaneseptember49770]

I did say sound sensible, gezzz

[shipwrightParticipant @shipwright]

Amy,

I came across this 2 stroke troubleshooting guide on the internet :

**LINK**

Might be useful for a novice but I doubt it would tell you something that you did not already know.

I hadn't appreciated that the air/fuel "charge" is compressed in the crankcase before being transferred into the combustion chamber – clearly a leaking crankcase gasket, cracked crankcase or crankcase bolts not tightened sufficiently can result in a weak mixture and therefore failure to burn in the combustion chamber. I'll stick to electric motors in my boats !

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Thanks Ian, most helpful!

I find the way engines work quite fascinating, and quite enjoy tinkering with them. I agree though, electrics are far less hassle!

I really appreciate the effort every one has made, and will let you know how I get on.

Amy jane

[Len Morris 2Participant @lenmorris2]

Dear Amy,

The smallest thing will kill small engines. Things that your car engine would laugh at for 30 thousand miles will stop a small engine in seconds. Do not jump in and imagine the worst (crankcase, cylinder head etc.) You have a spark and you have compression. The engine must pop and bang if it's getting fuel. Dose the inlet with either (it's called Bradwell's Easy Start in the UK) and prove the point. Then if you think the carbs ok, check all your fuel plumbing both for leaks and the correct connections. My garden strimmer died. Would crack up and then drop dead. Turned out to be a microscopic pin hole in the plastic primer bulb. Air leak and end off. Five quid to fix it and job done. Just had to find it. I'm sure you will to!!

Len

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Thanks Len. You are quite right,of course. Finding the problem is the problem!

Speaking of problems….. Murphy is having a laugh at my expense! Here's how my day went…..My normally very reliable car died five miles from work this morning. Quick road side diagnoses reveals no spark. Ok , reach for my cell phone, battery flat! Ok, it's only five miles, I'll walk. Of course I only have on my highest heels…totter on for a few miles, take a tumble on a bit of rough pavement and skin my knee. Walk the rest of the way in bare feet. Borrow my bosses car at lunch time and take a tool kit down to my car. Check distributor, plugs, leads etc. (no points to sand paper or condenser to squash). Nothing doing. walk a mile to the train station after work and head out to Lynn 's to borrow one of her cars. (Thankfully she met me at the station and saved me the two mile walk back to her place!) Drive the twenty miles back home…….

Oh yes, the boat!

Yesterday I took the carb and reed plate off, and inspected the reeds. They were a little bent, and I could suck back through them. Carefully bent them straight and got them to seal properly. Put just the reed plate back on and put a shot of ether down the plug hole and she fired. So I put the carb back on, and she ran for about 30 seconds and then stopped, and wouldn't re start. Cleaned the carb out , re installed and she ran good for about 3 minutes, before stopping and not re starting. I'll try swapping the carb/ reed plate with the generator next. (I guess I'd better sort the car out first)

Hopefully tomorrow will be a better day!

Amy j

[Paul TParticipant @pault84577]

Hi Amy

There could be a break in the HT cable, this would cause the intermittent firing that you are experiencing as sometimes the problem doesn't manifest itself until vibration or heat causes the break to part.

But from reading your comments it sounds more like a fuel problem and I would be looking for holes or tears in the carb diaphragm or a failed carb gasket.

Paul

[Bob Abell 2Participant @bobabell2]

Muck in the fuel sounds more like it!

Bob

[ashley needhamParticipant @ashleyneedham69188]

Probably bunged up with oojy-boojy wood sawdust

It is probably frightened as it was not designed to go as fast, or even on water come to that. Poor small industrial engine. It may just not want to be mistreated like this again.

Ashley

Just a thought.. it is petrol you are using?? you havnt found someones secret hooch stash?????

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi Ashley

The saw dust was wodgie bodgie. As for fuel, we don't have a local bp, so I had to use wasp urine, it's just not the same, you know.

More investigations have been undertaken, (I think the engine needs to be undertaken).

I was quite wrong about the reeds. I took the carb and reed plate off the boat, and put them on the generator. The generator started third pull and ran perfectly. So fuel/carbureration is eliminated. (I'm using fuel from the same can for both engines)

I've taken the engine out of the boat, and inspected the crankcase for cracks, and checked the crank shaft seals, all good.

Thinking on Paul's advice, The ht lead was inspected, but was fine, (there has never been a loss of spark) I've gone as far as removing the flywheel, using my patent Aj flywheel puller, (pick the engine up by the flywheel, and belt the backed off crank shaft nut with the hatchet, did that make you wince, Bob?), Just to make sure that the key hadn't sheared and the flywheel slipped and thrown the timing out. All was fine.

I also checked the tightness of the crankcase bolts, fine.

The one thing that don't seem right though, is with the piston at TDC, I can blow down the exhaust pipe, and clean through the engine, and out the carb intake. Hmmm I think the head's going to come off next….

[Amy jane SeptemberParticipant @amyjaneseptember49770]

oh by the way, this is what we call ether engine starter down here……

(there are photos of the disasembled engine on my bd boat album)

Aj

[shipwrightParticipant @shipwright]

Amy,

I thought that you said that compression was ok in one of your earlier posts ? Is there compression now ?

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi Ian

That is puzzling me, there is enough compression that I have to hold the boat down, when I pull it over, and also enough to blow my thumb off the plug hole, so there should be enough for it to run. Any thoughts?

Thanks

[Bob Abell 2Participant @bobabell2]

Oh dear!

I've got a petrol grass strimmer and it only runs when it feels like it!

it wouldn't start yesterday, which is the norm!……..But there is nowt wrong with it!

Your motor is probably the same and just being awkward and it's just a matter of plain hard graft

Why don't you simply give your present to Hubby and blame him for messing it up?

Fellas have a knack with mechanical things anyway and it may start, first yank!

If all fails……..Send for Lynn!……Or you'll have to read the handbook!

Bob

[Mark TommyParticipant @marktommy83416]

Hi Amy it sounds to me that a deeper look into the engine is required. The fuel and ignition systems sound fine and as the rotating timing has not moved it must be an internal issue.

At a guess I would say that the piston maybe damaged in some way or it could be that you had a partial seizure and the con rod may be slightly bent. This would put the transfer port timing out.

Also as its a two stroke generator engine you may find that the actual transfer ports are blocked up with old two stroke oil which would have the same effect. This would not explain the sudden stoppage though.

The nice thing is they are simple to pull apart its just getting the will to do it after the disappointment!

Good luck Mark

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