Rebuilt carb, now wont start...

[copelandcf]

I have a 2 barrel Merc carb for my 1989 Chris Craft Cavalier that I recently rebuilt. Now it wont start at all. I can see fuel going into the carb when I crank it but it wont fire. This was my first carb rebuild but I felt pretty confident in the end.

I rebuilt it originally because the boat would idle fine, but would cut out and stall at 2k rpms. When you looked inside the carb one of the bowls was bone dry and the other was wet, so I assumed something was clogged and rebuilt. I left the float alone and made no adjustments other than taking off and putting back on. All metal parts were soaked in berrymans for 20min+. There is a new needle and seat, but I reused the accelerator pump because they sent me the wrong style even though I asked for the "newer" bent style.

After rebuilding, I reset the dwell which seemed to be off a few degrees after rebuilding. The idle mixture and cam are set to initial settings. I did pull the plugs and interestingly enough plugs 3 and 4 were wet but 1 and 2 were dry. I dont know if this means anything or not. I would like to reset the timing but I cant get it running. Any ideas of what to do next? Am I supposed to put any fuel in the carb to fill up the float assembly? Thanks for the help. Cavan

 

[180shabah]

Re: Rebuilt carb, now wont start...

Got fuel and air, do you have spark? Has the kill switch been pulled?

 

[chiefalen]

Re: Rebuilt carb, now wont start...

And where is the adjustment needle now, Gently all the way in and out 2 full turns to start, don't bend the tip please.

180 asked if you got spark, ill ask did you soak it spray all the little holes CLEAN with carb cleaner and then dry with compressed air.

Was it for sure clean. And the filter at the fitting by the carb clean?

 

[dwyork@hotmail.com]

Re: Rebuilt carb, now wont start...

If you are getting spark and it ran before the rebuild then more than likely you are either lacking enough fuel (which is doubtful if you see the bowls filling up) or it is flooding. If the carb wasn't getting enough fuel in the first place and an adjustment had been made along the way by someone to get it to idle then now that it is presenting the correct amount of fuel the mixture may be off.

 

[Don S]

Re: Rebuilt carb, now wont start...

I don't know what berrymans is, but it doesn't sound like carb cleaner. Were all the passages clear? Have you ever rebuilt a carb before? Did all the parts fit properly? Carb kits comes with a lot of extra parts, did you put the right oines in?
With a professional doing a rebuild on a marine carb, the chances are about 50% that it won't work.

 

[chiefalen]

Re: Rebuilt carb, now wont start...

He didn't replace the accelarater pump was the wrong one in the kit.

Don s is as always 100 percent correct 50/50 chance that carb will ever run correctly.

Take it apart you missed something, no shame in it do it over. Something is clogged up.

Check the spark.

 

[copelandcf]

Re: Rebuilt carb, now wont start...

To be honest I dont know where the kill switch is, so I have not checked that. It had spark and fuel before the rebuild, so I just ruled that out. I can see fuel going into the carb when I crank it. I have not checked the spark but I'll give it a check but I have already replaced the points and condenser previous to this whole ordeal and it was working fine.

In my manual, it says 1 and 1/4 turns out from fully seated for the idle mixture. That is what I have it set at, the idle cam I have set at 2 turns in when the screw starts to touch the cam. These settings worked before when I first tuned it and I set the timing then. Now I can't get it to work.

Berrymans is a dip can carb cleaner at autozone, however I do not own a compressor so I did not dry the parts with air, but I did let them air dry. I did put in all the right parts, it was really simple. Its an OEM kit so they shouldnt be crappy parts, I know some aftermarket kits dont cut it sometimes.

The filters were dirty with sand and possibly resin flakes. I cleaned the fuel tank (the first big project for the boat) very thoroughly and its perfect. But I think there was some resin and sand in the pickup, or maybe even the fuel pump that got that grit in the carb and clogged it. I also checked the filter in the fuel pump and it had grit in it too. Both have been cleaned out.

I swear I'm losing patience with this boat. It ran fine, than the impeller went out and burned out the exhaust, replaced everything that melted and then it died on the lake, so replaced the ignition then it died again, this time clogged fuel filters, now clogged carb. I'm about to give up on this thing I cant even get 1 day on the lake in my first 6 months of owning.

Is there a baseline timing I should set, I just have it at the last setting I had working before this, even though I have readjusted the dwell and idle. But I do not know where to put it, any help? Or just leave it till it starts?

 

[bigbob_FTW]

Re: Rebuilt carb, now wont start...

I don't know what berrymans is, but it doesn't sound like carb cleaner.

Good stuff.

 

[a70eliminator]

Re: Rebuilt carb, now wont start...

I don't know what berrymans is, but it doesn't sound like carb cleaner. Were all the passages clear? Have you ever rebuilt a carb before? Did all the parts fit properly? Carb kits comes with a lot of extra parts, did you put the right oines in?
With a professional doing a rebuild on a marine carb, the chances are about 50% that it won't work.

Berrymans has been making carburetor cleaners for years my dad used the stuff way back when, it's poular with motorcycle mechanics, I've used it before and it works pretty good but the stink is horrable.

 

[chiefalen]

Re: Rebuilt carb, now wont start...

The worse it smells, and the more it burns on a cut on your finger the better it is. Hah.

Carb cleaner in a can under pressure, is good after dipping it. Go back do it again. " AFTER " checking for spark.

 

[Dunaruna]

Re: Rebuilt carb, now wont start...

..........After rebuilding, I reset the dwell which seemed to be off a few degrees............... Cavan

How did you test and then reset the dwell?

 

[ziggy]

Re: Rebuilt carb, now wont start...

while i'm no carb guru by any stretch of the word. my 2 cent is.
do soak (in carb cleaner) and clean carb. do wash in soap and water all parts that aint new. do blow dry with compressed air, especially the small passages in the crab. do use the correct carb kit (maybe even a oem kit). do replace any parts that are in the kit. for sure the acc. pump. while some parts may not need adj. do check to see if adj. is necessary making sure all adjustable parts conform to the specs for your carb. do follow your merc. service manual to the letter for the rebuild. also test the float for leaks. a sunk float won't work. do inspect any parts that move together for wear. inspect venturi where the throttle plates are for wear on the venturi itself.
i did these steps (the cleaning steps) twice on my last rebuild and was successful. or maybe ya got one of the 50% that ain't rebuildable. + since ya adj. dwell. your gonna have to reset this + the timing as dwell effects timing. good luck..

 

[Fishermark]

Re: Rebuilt carb, now wont start...

Berrymans is a dip can carb cleaner at autozone, however I do not own a compressor so I did not dry the parts with air, but I did let them air dry.

I would say the chances are good that you still have plugged passages. More so now than when you started. Soaking the carb is good - even necessary. But all the chemical will do is soften the gunk in the passages. That makes it possible to blow out the passages etc. By simply soaking the carb, now you have gunk that has settled in areas you probably didn't have a problem with before. It really isn't possible to rebuild a carb without some compressed air.

 

[chiefalen]

Re: Rebuilt carb, now wont start...

Sears has one 99 bucks 2 gallon model. Essential piece of equipment.

Once you get one you will wonder how you ever did anything without it.

My belt went on mine and that day i tried to get around not using it and i had to drop everything and go run and buy a belt.

Gotta say one other thing i don't think i ever got a carb clean the first time.

Soaked it carb cleaner in the can blow dry over and over till i was satisfied it was 100 percent clean.

 

[JustJason]

Re: Rebuilt carb, now wont start...

alot of carbs you don't want to soak in cleaner.

 

[Don S]

Re: Rebuilt carb, now wont start...

In my manual, it says 1 and 1/4 turns out from fully seated for the idle mixture. That is what I have it set at, the idle cam I have set at 2 turns in when the screw starts to touch the cam. These settings worked before when I first tuned it and I set the timing then. Now I can't get it to work.

Is that an OEM manual of one of the aftermarket manuals.
The mixture screws sound about right, but the idle cam worries me, don't you give it throttle when you start it? Don't you pump it a time or two to prime the engine? This is a Carburator, not EFI.
It also sounds (from your original post) that you may have had an accelerator pump problem to start with, and that is the only thing you DIDN'T replace. Might want to go back and replace it, and read the blue line in my signature.

The filters were dirty with sand and possibly resin flakes. I cleaned the fuel tank (the first big project for the boat) very thoroughly and its perfect. But I think there was some resin and sand in the pickup, or maybe even the fuel pump that got that grit in the carb and clogged it. I also checked the filter in the fuel pump and it had grit in it too. Both have been cleaned out.

You need to install a water seperating fuel filter, not just the filter in the carb. and it needs to be changed (and inspected) yearly at minimum. Even more often when you have crap in the system.

I swear I'm losing patience with this boat. It ran fine, than the impeller went out and burned out the exhaust, replaced everything that melted and then it died on the lake, so replaced the ignition then it died again, this time clogged fuel filters, now clogged carb. I'm about to give up on this thing I cant even get 1 day on the lake in my first 6 months of owning.

Basically, you are fixing things AFTER the problem occurs. You need to do a lot of preventive maintenance and inspecting to check things out BEFORE you start taking it out on the water.

Is there a baseline timing I should set, I just have it at the last setting I had working before this, even though I have readjusted the dwell and idle. But I do not know where to put it, any help? Or just leave it till it starts?

There are all kinds of setting that have to be done to makes sure it will run, but we have no idea what engine you have or anything else about it except you did mention it was an 89 Chris with a Mercruiser.
Have a look at the first post in the Adults Only sticky at the top of the forum

 

[copelandcf]

Re: Rebuilt carb, now wont start...

I used a dwell meter and feeler gauge, its currently set at around 30*.

I did use an OEM kit, but there are two variations depending on the style accelerator pump, otherwise they are the same kit. Unfortunately they sent the wrong pump even though I matched the kit to the carb number. Frustrating...

I do have an oem manual and followed it to the T. I will get a compressor and try again, I've been looking for an excuse to get one for a while. I'll get a new accel pump while I'm at it.

Don

I do pump to get some fuel in the carb, and give it 20% throttle to try and start it. I'll try and find a seperator for this boat. And sorry btw its a 3.0l 4cyl merc engine.

I'm not sure its the accel pump though because when we first got it running after replacing the points and setting the dwell and timing, it would run ok under acceleration all the way up to redline, it ran great in high rpms, but would idle rough and stall if you slammed the gas from on to idle. So we set the idle and mixture and timing on the water, under load. No more idle problems or stalling, but it would cut out above 2k rpms, and we noticed the one dry bowl, one wet bowl. Could that be the accel pump? Maybe it went out while tuning on the water. I figured it was a clogged carb, especially after I saw the grit in the filters, hence the rebuild. Thanks for all the help everyone, I cant wait to get this thing running right.


I still dont know where to initially set the timing, everyone keeps saying I need to readjust since I adjusted the dwell, but how do you set the timing without a running engine, trial and error??? Thats my only guess is trying different spots with the distributor. Let me know if there is a better way. Thanks again everyone.

 

[ziggy]

Re: Rebuilt carb, now wont start...

how do you set the timing without a running engine,

don't know if this is the right way to do it. but the way i go is, after dwell is set. i move to timing. ya only get close w/o it running. but i just crank it over while shining the timing light at it.. you should be able to see the marks. adj. distributor as necessary to get timing marks to where you want them... others may have a better way..

 

[Fishermark]

Re: Rebuilt carb, now wont start...

how do you set the timing without a running engine

You can simply turn the engine over by hand till the timing mark is lined up at whatever it should be - and that I don't know - your manual will say - I'm sure it should be in the 8 degree BTDC range. Anyway, as I said, turn the engine over till the timing mark lines up (being sure that the number one cylinder is on the compression stroke) - take the distributor cap off, turn the distributor body till the rotor is pointing at the number one spark plug cable. You now have it timed. Certainly close enough for it to run till you can get a timing light on it.

(If you don't know how to make sure it is on the compression stroke there are easy ways to find out - you have a 50/50 chance. Since it has already been running, then if the rotor is pretty close when you line up the marks I am sure you are on the compression stroke - otherwise it will be 180 degrees off).

 

[Ridemywideglide]

Re: Rebuilt carb, now wont start...

No more idle problems or stalling, but it would cut out above 2k rpms, and we noticed the one dry bowl, one wet bowl. Could that be the accel pump? Maybe it went out while tuning on the water. I figured it was a clogged carb, especially after I saw the grit in the filters, hence the rebuild. Thanks for all the help everyone, I cant wait to get this thing running right.


I still dont know where to initially set the timing, everyone keeps saying I need to readjust since I adjusted the dwell, but how do you set the timing without a running engine, trial and error??? Thats my only guess is trying different spots with the distributor. Let me know if there is a better way. Thanks again everyone.

I'm certainly no carb guru, far from it, but the accelerator pump is not the cause of your cutting out above the 2k range. More likely, the dry bowl.. Cutting out probably because it wasn't getting enought fuel. Most likely the small grit your talking about plugged up some obscure passage.
I'll be in your shoes this weekend when my carb kit gets here, only I've got a 4 barrel. Even more stuff to screw up..