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MERCRUISER 30L RUNNING VERY VERY RICH HELP

J

juzzac

Member
"G'day Everyone,
I am hop

"G'day Everyone,
I am hopeing someone will be able to help me with a possable carby issue I am having.

I have recently purchased a 2002 bayliner 175 with a 3.0l 4cyl mercruiser engine, The boat had completly sunk in salt water and was not serviced after it was recovered, I removed the engine and rebuilt it. I also replaced all the wiring connectors, switches, and everything electrical that was damaged by salt water, I have replaced all bearings and seals in the sterndrive, I replaced the iginition coil, dizy pick up coil and module, I purchased a rebuilt carby from the USA that was meant to be a bolt-on replacement for my mercarb, It is called a rochester, I finaly got it all back together and running this weekend and all is good except the engine runs very very ritch and rough due to the ritchness, The grass at my girl friends place where I have had it running is sooty black ( she is not very happy with me)
and the area around the exaust on the hull has also turned sooty black, You can also smell the unburnt rich smell when its idleing and when u accelerate, The engine can sometimes be very hard to start when cold and I have to disconect the linkage from the throttle cable and hold it about half open to get it to start as it just coughs and splutters otherwise. I followed the timing procedure in the manual and the timing is spot on. I have emailed the person that I purchased the carby from and he advised he thinks my fuel pressure is to high, I checked the fuel pressure today and it was around 6 psi, he says it should be about 4-5psi, Mercury say it should be 5 1/4 to 6 1/4 so I don't believe this is the cause as I also ran the engine for about 30 seconds on the fuel in the bowl with the fuel pump disconected and it still ran very ritch, what I have also noticed is a very strong unburnt fuel smell from the breather hose coming from the top of the rocker cover. The choke operates as it should, There seems to only be a idle mixture screw on the bottom of the carby which makes no real difference to how it runs. how else would I adjust the mixture ?? would I have to replace the main jets with a smaller size ?? if so does anyone know if the Mercarb jets would be the same as a rochester? The carbs visualy look the same. what else should I look out for in the carb?? I have had very limited to do with carbs in the past, 99% of my mechanical experence is on injection. does anyone have any other suggestions to the rectify the richness ??

thanks Juz"
 
"Ayuh,........

My 1st Guess

"Ayuh,........

My 1st Guess is,......

The Float Level is Too High or Too Low......."
 
Juz
I go with Bondo. Float no

Juz
I go with Bondo. Float not set right or a poor rebuild. Have another carb sent over that is rebuilt properly.

Bert
 
"Thanks Bondo and Bert for you

"Thanks Bondo and Bert for you suggestions, The person that rebuilt the carbys hasn't replied to the last two emails I sent him so I decided to take off the top of the carby and have a look, I measured the float drop and it was 27mm which is the exact spec that mercury suggests, I then inspected float and so on all was good, I removed one of the main jets and found the number 165 or .65 on the surface it is hard to tell as the rebuilder looks like he damaged it on removing it. the other jet had a very badly damaged surface and had no marking left on it. (the merc specs say 1.45mm for the 36mm type carby or 1.55mm for the 43mm carby.) it also had a power valve with the marking 90 on it. (the merc specs say 2x 0.60 , which I don't understand as it only has one power valve)
can someone please tell me how I can tell if I have a 36mm or 43mm carby? do I measure the throttle body bore ?? Do you think a .1mm or .2mm larger jet would give me such a rich running problem?? thanks Juz"
 
Juz
Have you checked the need

Juz
Have you checked the needle and seat on the fuel inlet for a foreign object caught there? On the Rochester I believe there is a number stamped on the underside of the throttle body.
Bert
 
"Hi Bert I removed the needle

"Hi Bert I removed the needle and checked for dirt, no luck, I have cleaned and blown out with compressed air just in case, the needle seem to seat ok with no leaks, do you think the oversize jet could be my problem with the excessive richness ??"
 
"Juz
I don't have much ex

"Juz
I don't have much experience changing jets out in carbs. I've always been satisfied with what the manufacturer installed. From what you're telling us the rebuild seems to be a bit of a hack job. There are a plethora of small, under the screw head, gaskets and several different bowl gaskets that go into these carbs that may have been mis-used. The way you describe the richness it seems to me it's a catastrophic problem not a mere adjustment problem. If the power valve is malfunctioning it will load a lot of fuel into system.
Have you found a reference number for the carb yet?
BTC"
 
"Hi Bert yes I got a these num

"Hi Bert yes I got a these numbers of the side of the carb 807312 and the built date is 03/nov/05
a google search shows the part number to be for a 5.0l engine it also shows that the jets should be a 1.65mm which they are and the power valve should be a .9mm which I guess the 90 stamped on it stands for, so It looks like I have been sent a carb for a 5.0l engine instead of a 3.0L engine, I would say thats why I am running so rich, I have spoken to a carby shop in Australia and they said they can make the jets in the smaller size for me, he wasn't sure if there was any other differences in the carby between the 5.0l and the 3.0l
I have emailed all this info to carbcareusa where I purchased it from and was told it had a 6 month warranty, but have still had no reply."
 
"Following along. Agree. Sound

"Following along. Agree. Sounds like you've got jet issues. Can you use the jets from the old carb? In a pinch, I have peened the top of a jet to reduce its diameter and then, using a set of micro drill bits, progressively increased the diameter of the bore until i get the mixture right. Just a thought. Good luck. Let us know if we can help browbeat the dealer here in the states."
 
"Gents.:

Per the chart on

"Gents.:

Per the chart on this web site the #807312 relates to a carb for a 96-97 5.7L.

Juzzac:

Do you still have the original carb? There should be an aluminum colored tag on top of the carb with some numbers on it and numbers on the side of it. Using those numbers, buy a carb kit for it from this site and rebuild it. It is simple. Use a digital camera as you dimantle it piece-by-piece. By a Merc. manual for your year engine and it has the procedures for a rebuild.

I can't think your orig. carb needed much more than an internal cleaning, accelerator pump, float and needle valve to put it back into service. YOU CAN DOOOOOOOO ITTTTTTTTT!"
 
"Hi, thanks for the replys, I

"Hi, thanks for the replys, I do have a merc manual which was very helpful in rebuilding the engine and stern drive. I do still have the original carb, I have taken some photos to show you what the inside of my carbs look like, this is why I didn't attempt a rebuild, I would have to also drill out a couple top air horn bolts that snapped on removale. As you can see in the photos that the jets are going to be a bit hard to remove and reuse
131150.jpg
"
 
"Maybe someone swapped carbs o

"Maybe someone swapped carbs on you one night.
blush.gif


Where in the world was the carb? In a salt bath?"
 
"Juz
I agree with Mistahays,

"Juz
I agree with Mistahays, post the re-builders info and maybe some one can stop in and have a chat with him/her. If nothing else I'm sure they wont' appreciate the advertising.
Bert"
 
"Hi,
Yes it had a salt bath/s

"Hi,
Yes it had a salt bath/some of the ocean in there when I opened it up. I ordered some 1.45 and 1.55mm jets from a carby shop in australia but recieved them today and they were to large
I will ring them again on monday and see if they can get the smaller type for my carby.
If I have no luck I might try Mistahays Idea about peening the jet and redrilling out with micro drill bits as the genuine jets from mercury australia will take 4 weeks to arrive.

The carby shop in the usa which sold me the wrong carby was called carbcareusa
www.carbcareusa.com
They haven't replied to any emails in over a week, I have put a paypal claim in against them as the carby was not what it was meant to be and they haven't even bothered to respond to that.
Thanks again everyone for all your help and I will let you all know when I finaly get the correct jets installed."
 
"if you paid va a credit card,

"if you paid va a credit card, you can go that avenue to resolve. its taken very seriously by visa/mastercard. just a thought."
 
"UPDATE !!!!!!

I recieved t

"UPDATE !!!!!!

I recieved the 1.55 and 1.45 main jets today, I also purchased a .65mm power jet to replace the .90, I also upgraded the needle and seat to a 3 piece set that has a spring on the needle, I have read that will reduce the chance of it running ritch at idle, I started off by installing the new power jet, needle and seat and the 1.55mm main jets, it ran much better, the idle was a lot smoother but still to ritch, I then swaped the jets with the 1.45mm jets and retested, the Idle was perfectly smooth but when I accelerate the throttle while in neutral it bogs down and backfires through the carby, I adjusted the idle mixture which improved it slightly but still back fires, I think I might bother the carby guys again and get them to drill me a 1.50mm jet and see what happens, I also forgot about the power jet lever has three holes which you can make ritcher or leaner, I might also try the ritchest setting, anyone got any suggestions or do you think I am on the right track with the 1.50mm jets ????}"
 
"thanks for the info on the cr

"thanks for the info on the credit card Mistahays, they still haven't bothered to reply to the paypal complaint, They have untill the 22nd to respond or paypal will refund my money I hope!!! if that doesn't happen I will go to my credit card bank and see what they can do.
thanks Justin"
 
You may want to pull and clean

You may want to pull and clean your plugs; may be too fouled with soot and interfere with ignition spark.
 
"Thanks Guy you were spot on a

"Thanks Guy you were spot on about the fouled plugs, cleaned them and ran it for about another 10mins without a backfire, then they sooted up again and back to square one with rough idle and backfire, I am so over this carby, I hope paypal will refund me, I will then go and buy a brand new one.
angry.gif
"
 
"juzzac;

For what it's

"juzzac;

For what it's worth, if I were you I would threaten to blacklist the original carb shop on this and every other marine chat site. You can cause them a lot of bad press, and maybe get to come to the table and make it right.

They probably figured that since you are a long way from the US that they could screw you around and ignore the problem and it would go away.

In this age of immediate worldwide internet communications, however, it is not in anyone's best interest to simply ignore a problem with a customer.

You have paid your money, they have not delivered, now they are ignoring your communications, and that is just plain wrong.

I would threaten to make their lives as miserable as possible until they make it right. You have nothing to lose.

Just my thoughts,
Rod"
 
"[url=""]www.carbcareusa.com[/

"www.carbcareusa.com

If everyone on this site sent an email to them expressing how dissapointed you are in the manner they have treated a member of this board they may respond. Mine is going to them today."
 
"Here is their email address a

"Here is their email address and what I sent them.

Customer Service: [email protected]

A friend of mine in Austrailia recently bought a carburetor from your firm. Many of us have tried to help him with what you sent him; an apparently defective and/or wrong carburetor. He has expressed your lack of responce to his numerous emails. I am a senior member of a world-wide Marine Engine Advisory Board with thousands of members around the globe that read the marine engine problem discussions posted daily. I thought you should know your company's name has been getting mentioned as one with a "less than responsive customer service". I am disapointed about your choosing to ignore his emails, your "company's less than responsive customer service" and failure to respond and remedy your mistake in a timely manner.

Senior Member
GuyG"
 
"Rod:

Thanks. It can't

"Rod:

Thanks. It can't get anyone in trouble since it tells the truth. I enjoy writing; my 1975 college english professor asked me a year ago when was I going to publish my first book; you have no excuse now that you're retired, she said. Don't know yet, I said. It'll come to me light flipping on a light switch; always has and then I won't stop working until I am finished.

All Others:

Feel free to copy what I sent; just change as needed. Guyg"
 
"Hi All
Got a reply from the

"Hi All
Got a reply from the Carb guy.
"i only got one email from him,and i responded back telling hime what to do, i find it unfair that you are giving me a bad reputation when, i havent had a chance to even find out anything about that carb"
We may have a communication problem here??
Bert}"
 
"Here is the reply I got.

R

"Here is the reply I got.

RE: Failure to respond‏
From: Hector Gonzales ([email protected])
Sent: Thu 12/20/07 2:36 PM
To: [email protected]

i dont apreciate your email telling me i dont deal with my customers,the only person i can imagine is on australia and i have sent him several messages thru ebay about his problem,so before stating that i dont handle my customers i think you should 1st email me and ask me."
 
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