1989 Bombardier, Wont start.. Read forums, went through basics and nothing.

[b0b88]

I picked this old doo off of craigslist with the intention to tinker and see if i could get it going again... I havent been twiddling my thumbs, i'll run you through what I've accomplished already.

First and foremost I emptied the gas tank and the oil tank and refilled with new gas/oil.
I tested compression in both cylinders, 125 for both (I think thats ok? yes?)
I checked for spark *check*
I checked for fuel, Negative... I cleaned out the fuel selector and mech fuel pump/filter.. Doo now has plenty of fuel flowing to the carb *check*
I reset the low speed oil mix adjuster to two turns out, I could not find the default setting the the idle adjustment screw or the high speed adjuster mix.. also there is a screw with a spring around it under the high speed adjuster that i have not been able to find any info on the forum as to what it is/does.

now that all the basics have been covered (I think)

Upon trying to start it the carb backfires from the air intake (small burst of flame) every few seconds

now is where i've hit a deadpoint, I realllllllly don't want to take apart the carb... but it has been sitting for some years....

Any help/ideas will be much appreciated!!!

 

[b0b88]

Also is there a recommended plug for this Doo other than the Champion RN4C spark plugs with a 0.5 mm gap, which is what i found on ehow (which i don't trust lol)

 

[RodInEscondido]

NGK BR8ES or BR7ES plugs work for me

125 compression is low, 150 is ideal and down to 140 is still good. Should still run at 125 according to the experts here, but time to be looking at rebuild. If, as you say, it has been sitting for quite a while I would recommend get it to a stage where it will run for a minute or so using premix, let it cool to cold, then make the compression test with throttle wide open.

There is a sticky at the top of this site regarding carb work; excellent piece. You may get away with cleaning out the innards of the carb, not really difficult.

Download a shop manual, either here as premium member or several other places on web.

I am very concerned about backfire and flame in engine compartment or I would make the typical suggestion of pouring a couple tablespoons of 40:1 premix down the carb, replace the air intake/flame arrester and try to start it; it should act like it is running for a couple seconds. If it runs for this short time it pretty much tells you the major problem is gunky carb.

Shop manual will show what that spring is or post a picture here and it will be identified. My initial thought is that it is the return spring for the oil injection pump.

What part of CA?

Welcome aboard the best SeaDoo site; I personally have gone from knowing absolutely nothing about SeaDoos to my current state of knowing very little about SeaDoos by participating ... this is progress. Keep smiling and have fun.

Rod

 

[b0b88]

The screw in question is the red one on the Lower left hand side... I could not find it referenced in the manual...

Also I could not get it started by pouring a couple teaspoons of gas into the carb, I am going to gently clean it up now.

 

[b0b88]

Sorry I did not completely respond to you ron, we had to pickup our foreign exchange student at the airport yesterday... I'm up in the Sacramento area I have gone through the carb and cleaned out a little of the gunk, It would still not startup after that... after reading many websites I decided to take a look at the rotary valve to verify that it is spinning and here is a video the test.

[video=youtube;Z5EYHqGDlpw]https://www.youtube.com/watch?v=Z5EYHqGDlpw&list=UUvk0eO67xg4M2vNDxnFrKGA[/video]

could i just have weak spark? or maybe a flooded engine? or possibly water got into the engine? or would the timing be that far off that it would not even turn fire off a couple times??

I decided to be a little brave/stupid and hooked up the key and tried starting it right after this video and the thing backfired and singed half of my arm hairs HAHAHA :facepalm: anyone have any ideas?

 

[RodInEscondido]

The carb in the picture does not look like the ones on my 2 89 SPs, I do not know what it is. One of the real experts out here would need to jump in and maybe give a hint. I do not want to take a guess on this piece.

The engine pic/video shows a head cover (indicating probably a different head also) that is not stock. I will follow this post, but do not think I have the experience do deal with these modifications. Sorry about this.

The above being said ... I would suggest checking the rotary valve for proper type, gap and timing. Likewise for the mag timing (which I have not done yet, but seems rather straightforward in the manual).

Sure sounds like you have enough spark to set off some fuel.

Rod

 

[b0b88]

anyone have a tip for recovering bolts from under the engine mounting plate lol?

 

[RodInEscondido]

anyone have a tip for recovering bolts from under the engine mounting plate lol?

Jake and I can verify that nobody out here has dropped anything down under the engine (bilge), correct?

Magnet

push rag under engine front to back

buy new bolt

pull engine

have fun

Rod