Aq131d cylinder head question

[rdengil1]

Well after months of trying to work out a back fire issue, I decided to tear the engine down and do some cleaning. I also decided to get a new carb which I recieved today, came ready to install from the box. I also picked up a cylinder head in excellent condition from a running aq151, here is where the question comes in...my cylinder head is cast 1000531 the one from the running boat is also the same cast number, is there any issue with swapping the two? Thanks.

 

[rdengil1]

Re: Aq131d cylinder head question

well they look identical so I will swap and see what happens.

 

[rdengil1]

Re: Aq131d cylinder head question

Wow. I must be one screwed up DIY'er. Got the engine together, finally had a nice day to start the thing. No issues, fired right up and idled around 1100 rpm. I adjusted the idle screw back to 900 rpm, turned the distributor a bit to get the 6 degrees. It idles up and down...first sounds like its going to stall (rpm dropped to about 800) then revs up to about 1200. Not sure what is going on, this has been a 2 year project, I completely stripped the engine and cleaned and greased everything, even ordered a new carb and put on a new cylinderhead, ensured all timing marks were lined up and then hoped for the best. Well I at least got it to start. What I did notice when putting it together was that when all marks were aligned and the engine was at top dead center, the timing plate went on and the mark on the crank pulley lined up with the timing cover (outer one with the degree marks) at 10 degrees, should this have acutally been 0 degrees first and then adjusted to 6 degrees when running at idle? I have no idea what I am doing wrong. starts great, try to apply throttle slowly and it wants to stall. If I quickly apply throttle it chugs a bit then goes, just can't apply it slowly or it dies. Not sure what would happen if it was under load. Please help. I hate that it looks this good and I can't use it again. Thanks. Dennis. I have two videos but they are too large to attach.

 

[rdengil1]

Re: Aq131d cylinder head question

Well tried to adjust the carb air mix, and turn dist. No joy. Have the battery recharging as I drained it trying to start it all day. All timing marks are aligned correctly, plugs are new and properly gapped. Carb is a rebuilt carb from a reputable dealer, distributor has an electronic ignition (hotspark). I got close to it starting, but then nothing, it starts after giving it some gas then dies. I pulled the distributor out completely and placed the rotor pointing to the number one plug on the cap and then rotated it clocwise 1/8 of an inch and then placed it in the block, it wanted to start, i moved the dist back and forth and kept trying to start, it will crank, fire and die, then depending on which way I move the dist it will just crank and not fire. I realize this thing has no choke and is hard to start when cold, but this is rediculous. I have been spending so much time trying to fix the issue and get it to crank and run with no luck. Not sure what else to do, the cylinder head is rebuilt, the carb, new fuel pump, tank, lines, plugs. I can't believe that it is this difficult to time the engine. I have great compression, spark, and fuel. I had it running the other day, but once it stopped, I couldn't get it restarted. So frustrated. I timed and retimed this thing so many times with no luck. Any other ideas would be appreciated. Thansk. Edit Post Reply Reply With Quote

 

[Robj]

Re: Aq131d cylinder head question

You needto check the basics, is the valve timing right on, the running problem may be due to vacuum leaks, also check for fuel.

 

[Technorunner]

Re: Aq131d cylinder head question

Iworked with one this late summer. when it was cold out. we had to pump with throttle for about a good 5 mins until it would idle. Because of no choke on it. Se if you can do that to get it to run until it gets a little warm and see if its idle then!