No Throttle

[hal5778]

Hello everyone I hope someone can help with this problem. I purchased a 96 Sportster with the single 717cc Rotax at the time of purchase it was blowing a water and oil mixture out of the spark plug holes so I pulled the motor and flushed out the block using a mixture of gasoline and oil which seems to have done a decent job on removing any water or contaminated oil. I reassembled the motor using new Orings on the head and head cover and torqued the bolts to specs and sequence. Are the ONLY gaskets required the Orings and not a normal head gasket? Should I put some kind of sealer on the surfaces of the head and head cover? My problem is the motor will start but at an idle it seems to surge up and down on the rpms and when I accelerate there is no response to speak of seems like the motor is bogging down. I have drained and added fresh fuel,cleaned the carburetors,checked the timing (set to 159 degrees) and really dont know where to go from here any help would be greatly appreciated

 

[etemplet]

Just the required gaskets, no sealant to apply. I usually put a little water resistant grease on the o-rings prior to assembly (A very small amount) Sounds like you're not getting fuel or getting way too much air. I'm curious as to how the water and oil got in there and wondering if the crank seals are leaking,

 

[hal5778]

not sure how the water got in the motor the person I bought it from never used it he was going to repair but sold instead. The motor currently is not blowing anything out the spark plug holes and when I increase the throttle and spray fuel in the carbs it doesnt change the issue. If I am getting too much air what could be causing it I made my own carb base gaskets and cleaned the carbs

 

[mikidymac]

What’s the compression?

Also per the manual the cylinder o-rings should get a little Loctite 515.

 

[etemplet]

Perhaps I should read more. LOL Now I know why those gooves are so difficult to clean.

 

[hal5778]

Hi mikidymac and thanks for replying the compression is 150 on both cylinders. I took the carbs off again today and cleaned them but they really didn't look bad except it appeared to have a little water in the pump assembly. I reinstalled the carbs and still am having the same problem. Just curious but on both carbs there is a needle adjustment that has a plastic cap that only allows you to turn the needle valve appx one third of a turn when I removed the plastic cap the needle valve seemed to be tightened all the way in I counted the turns while taking them out which was appx 10 full turns and I blew out the hole and reinstalled them turning ten in until they seemed to bottom out I don't know about these valves but if they are for air mixture most all I have ever dealt with you bottom them out then turn the valve out somewhere between 2 and 4 turns?

 

[mikidymac]

You really need to get that water out and find the source. Also pull the kidney shaped plates inside the carbs because water can sit in there too.

I have chased water in the carbs before and it can act really strange. It is heavier than water and thicker so when you give it gas it will get suckled up into the jets but is too thick so it chokes the engine off. Then when the engine stalls the water sinks down until you get enough throttle to suck it into the jets again.

I spend an entire weekend in the 90's fighting this until I pulled the kidney plate and saw the little ball of water.

 

[hal5778]

Yes I did pull the kidney shaped plate and cleaned it as well although I didnt see anything of concern. I noticed today that I had water drippipping out of the seam between the head cover and the head I am going to run it again tomorrow and then retorque the heads to the 17 ft lbs and see if it stops. I evem took the gas supply hose off and drew gas through it to inspect for water but it appeared to be okay I thought that perhaps even though I drain the tank there could have been some water left in the tank and got mixed in with the new gas I added. This one is a puzzler for me. Also at low rpms the motor seems to surge up and down on the rpms not sure about the high rpms havnt gotten there yet.