YAMAHA jet 2T engine MIKUNI SBN carburator rebuilt kits EU source?

vas

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title says it all really.

As part of refurbishing the avon jetrib I recently bought, I want to purchase rebuilt kits for the two MIKUNI carbs on them (as well as buying a primer kit to improve cold starting)

Problem is that I cannot find any cheap sources of such kits in the EU. Don't want to buy from HK or China, as I'd like to test that at the beginning of Sept, and I don't want to buy from US.
Anyone knows of a decent/cheap(ish) source of such kits in the EU?
A UK guy hasn't replied yet, and I've got a fairly expensive shop in FR and a reasonably priced one in DE (but experience is that DE delivery is annoyingly slow...)

cheers

V.
 
Does anyone offer any sort of carb upgrade ? Most Avon ribs I see ( and it is not just an exprsssion it really is most ) have the hood up and then start with a cloud of smoke only to stop again.

I guess it is carb issues 2 strokes are simple things.
 
:D
you're absolutely right J.

I spent a few days looking at posts on PWC forums, (there are serious nutters there!) and considering the Yamaha 2T 2cyl engine is a v.simple thing, I see that the main issues are carb tuning solution: new seals/membranes/etc (circa 80euro for two carbs) plus the primer kit to replace the awful choke to improve (or rather enable!) cold start...
Seems that the old jetskis that work have the two above things and that's what I want to do ;)

cheers

V.
 
Hi
These engines are identical to the ones found in older Yamaha waverunners. Usually a 700cc, 800cc powervalve or occasionally a 1200 triple. Great engines with the right care and a top end rebuild every 100hrs. I have one in the garage in a GP800R
The carb kits are readily available from a few favourite vendors like preben jet ski and stirlings marine. Not cheap at around £80 for the 2 cylinder engine. If it’s just showing typical carb problems take them off and stick in a ultra sonic cleaner for a while. Usually does the trick without a full rebuild. If not, just find out what engine if the above it is and treat as a jet ski engine. eBay will certainly have them but best speak to the experts like preben. Stirlings or jet products in NI. The latter two being the foremost Yamaha 2 stroke experts in the U.K. without doubt.
 
Given what else you have accomplished this will be a walk in the park!

that's what I thought and one of the reasons I bought one when everyone was saying no don't do it...

Try here, I have bought from them a few times.

https://www.lineonedist.co.uk

Or

https://www.ncjetski.co.uk
thanks a lot, these guys are selling original MIKUNI kits at 80 and 60quid for each carb respectively.
I have to evaluate if the original mikuni against the various others that are on sale offer something more.
Considering the avon was mostlikely on it's original filter for 17+yrs, I can live with 30euro per carb kit that I may have to replace in 6-7yrs...

Hi
These engines are identical to the ones found in older Yamaha waverunners. Usually a 700cc, 800cc powervalve or occasionally a 1200 triple. Great engines with the right care and a top end rebuild every 100hrs. I have one in the garage in a GP800R
The carb kits are readily available from a few favourite vendors like preben jet ski and stirlings marine. Not cheap at around £80 for the 2 cylinder engine. If it’s just showing typical carb problems take them off and stick in a ultra sonic cleaner for a while. Usually does the trick without a full rebuild. If not, just find out what engine if the above it is and treat as a jet ski engine. eBay will certainly have them but best speak to the experts like preben. Stirlings or jet products in NI. The latter two being the foremost Yamaha 2 stroke experts in the U.K. without doubt.
Correct! wasn't aware of the top end rebuilt but I can live with that (extra fun...)
I made the mistake to ask the seller to drain the whole system of fuel before shipping. Left with no fuel for 5months now things are dried and check valve was stuck. I'll do the UltraSound cleaning as well, but I think it's worth a new set of seals all around.

However I didn't realise it would be so difficult to buy the kits!
preben have good prices but wont ship to Greece.
Jetproducts is away till the 4Sept (and I'll like to fit them on that w/e)

I've emailed a few and waiting for replies tomorrow and then I'll proceed with the order.
Seems that the most reasonably priced shop is the jetskicentre.co.uk

talking about avon jet ribs, I wonder if there is a specialist or stockist as I also managed to break and loose in Alonissos port the bow green-red navlight (fouled on next boat's sternline that was overenthousiastically stretching over my bathing platform and the wake of a ferry managed to mess the whole thing up)

cheers

V.
 
Hi there.

I’d look at stirlings or any decent Yamaha ski dealer. They will sort you out no bother.
With regards to the top end rebuild. Yeah defo do it every 100 hours. It’s honestly not a bother at all. So easy and actually a pleasure to work on these wee things. Well engineered and the manual is superb.
Not sure if I said above either, but 100% get the oil injection block off kit and pre mix the fuel at 40/1 the oil lines are well known to perish causing total failure and a total rebuild at hefty cost. Piece of mind. It will fail at some point. Nothing surer. Also easy to do. 10 minute job and less than £20 for the kit.
 
thanks QBhoy!

finally ordered rebuilt kits and primer kit from jetskicentre.co.uk, the only outlet that had both items in stock.

Now regarding the block off kit and top end rebuilt, do you actually have any pdfs or urls with explanations and how tos?
I mean it's easy enough to remove the top end of this thing, but tbh not sure what I'll be looking at other than removing lots of salt deposits from the liners (not sure if cyl head is cooled or not).

I have the AVON manual but it just gives general info on maintenance. My engine is the low power 80hp 2cyl one.
I'd really like a decent yamaha service manual I mean how to take the thing apart, torque values, tolerances that sort of thing!
Is there something like that floating about?

cheers

V.
 
Yeah. Loads of manuals online. Just need to find out what engine it has. Likely the 700. Google Yamaha 700 xlt manual. Send me a picture of it and I’ll likely recognise it.
The oil block of is real easy. On the front of engine there is a mech driven pump with 2 bolts holding it on (really obvious once you get the kit). Undo these and pull pump out. Cable tie it up out the way and fit the blank piece. Empty the oil tank and cable tie the float level sensor up or leave full of oil (bit of a waste this way though) need to do either or to stop the alarm going off. Pre mix the fuel tank at 40/1 mix. (400ml in a 20l tank of fuel).
Once you get the manual it’s a real joy to work on these wee things. Really well engineered. The actual cylinder head isn’t water cooled exactly but the pots are in the cylinder jackets where they meet.
 
thanks again QBhoy!

engine sticker says 1YMXM-7013CB

only got a pic with the top of the engine atm:
avonjetrib_engine1.jpg


EDIT: OK, looking around I found another sticker J700G
avonjetrib_engine2.jpg


I understand that means the 700cc one, correct?

looking around I did get to:
http://www.yamaha-motor.com/assets/service/manuals/2002/lit-18626-04-39_296.pdf
which seems to fit, but it's not a service manual and some of the stuff in there are already in the AVON owner's manual.

cheers

V.
 
Last edited:
Hi
Sorry it’s takem so long. Yes. Instantly recognisable as the 700cc yam 2 stroke.
Also world renowned as one of the most reliable 2 stroke engines out there.
Look up the manual for a “Yamaha waverunner xl700 or xlt700”
Literally loads of info, manuals and YouTube stuff online for these.
 
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