Merc 3.0 carb cost?

[thompson80]

Re: Merc 3.0 carb cost?

Maybe find a new "rebuilder"? On my old 2.5l with 2GC I could throttle it however I wanted and it would respond like it was supposed to. I did the rebuild on the carb myself.

Shop that installed the rebuilt 140 sent the carb out to his trusted carb shop for the overhaul/rebuild, so I don't want to doubt that work... yet. I didn't get a chance to talk to him today, will try again in the a.m. I have been using ethanol gas, so just added 10 gallons of ethanol-free marine gas to the 20 gallon tank to top it off. That will be my next test, unless I get other advice. When the engine was rebuilt, the original accessories were all re-used: starter, alternator, distributor, coil, etc. So will check the distributor cap, rotor, (I THINK they're new, as are the points, & condenser) advance mechanism, gap, dwell, and timing when I get a chance. Reading old posts, I read one who recommended advancing the timing 2 degrees, but will see where it's at first before experimenting with that. Another recommended 92-93 octane gas - said that made a difference for him. Since it idles well when warm, and accelerates fine once I get past about 1200-1500 rpm, and runs fine at WOT, I'm not doubting the fuel tank pickup, anti-siphon valve, vent, etc. Will check the fuel pump filter (if it has one? 1980?) - dunno if the shop did that. He did say the filter at the carb was clean when he took the carb off.

 

[fishrdan]

Re: Merc 3.0 carb cost?

Shop that installed the rebuilt 140 sent the carb out to his trusted carb shop for the overhaul/rebuild, so I don't want to doubt that work... yet.

While the rebuild might have been done well, what about the parts they used?

I have a 72 140 HP and have rebuilt the carb 4-5 times since I owned it, 15 years. 2 rebuilds back everything ran good in the driveway hooked to the muffs, but it crapped out on the lake a couple weeks later,,, huge bog right off idle?!? The accelerator pump was brand new, so I knew that couldn't be the problem, right? NOPE... When I popped the top off the carb the acc pump was stick in the bore, lipped seal had swelled up :facepalm: probably due to the plastic not tollerating ethanol. Luckily I had the old parts in my tool box and swapped it with the old acc pump and I was back in business. The carb kit I used was brand new, but it had substandard parts that were not compatible with ethanol.

Run the engine bit to get the carb full, then with the engine not running, remove the spark arrestor, hold open the choke and have someone push the throttle wide open while you look down the carb, you should see 2 steady streams of fuel shoot into the carb bores,,,, from the accelerator pump.

 

[thumpar]

Re: Merc 3.0 carb cost?

We use ethanol fuel because that is all we can get, but like fishrdan stated, some parts don't hold up to it.

 

[stonyloam]

Re: Merc 3.0 carb cost?

We use ethanol fuel because that is all we can get,

Ethanol free gas is available almost everywhere, look here: Ethanol-free gas stations in the U.S. and Canada Some of marinas have it. It may be a bit of a pain to get it to the boat, but I think it is worth it. My boat loves it!

Thumpar, there are at least 3 stations in Spokane.

 

[thumpar]

Re: Merc 3.0 carb cost?

Ethanol free gas is available almost everywhere, look here: Ethanol-free gas stations in the U.S. and Canada Some of marinas have it. It may be a bit of a pain to get it to the boat, but I think it is worth it. My boat loves it!

Thumpar, there are at least 3 stations in Spokane.

The lake we go to is 11 miles from our house. I would have to drive and over an hour just to get gas and they charge crazy prices for ethanol free around here. Washington state is crazy about the stuff. My boat is fine with the ethanol and I use the green Sta-Bil just to be sure.

ETA: Sorry not trying to take this off topic.

 

[fishrdan]

Re: Merc 3.0 carb cost?

Ethanol free gas is available almost everywhere, look here: Ethanol-free gas stations in the U.S. and Canada

Almost..... Looking at that websites map I'd have to drive to AZ or UT (2 hours) to get ethanol free fuel :facepalm:

 

[thompson80]

Re: Merc 3.0 carb cost?

While the rebuild might have been done well, what about the parts they used?
(snip)
Run the engine bit to get the carb full, then with the engine not running, remove the spark arrestor, hold open the choke and have someone push the throttle wide open while you look down the carb, you should see 2 steady streams of fuel shoot into the carb bores,,,, from the accelerator pump.

Will do that test, hopefully Monday, when, wx permitting, I hope to go out with a friend.

This morning went to talk to the shop owner that did the engine rebuild. He's a Mercruiser master tech, but hadn't heard of the modification of boring out the "ports" below the accelerator pump. He gave me the name of a local carb shop to inquire about it, and the guy at the counter said, "Sure, we can do that. It's about an hour, $99." The carb guy also said, "We try to hold them to 0.040" (and he didn't call them "ports" but used some other term I didn't catch) so I called back and reported that to the Merc tech. So obviously, people ARE getting this modification done, to compensate for ethanol blend gasoline.

Before spending more $$ modifying a freshly rebuilt carb, first I'm going to try out the 50/50 mix of fairly fresh ethanol & ethanol-free tank of gas I have now, and then refill with ONLY ethanol-free gas again when I refuel for a couple tanks. If no improvement, or even if there is, I may play with the timing some, too. The Merc tech says he starts out a bit conservative, timing this engine at about 6 degrees BTDC to stay away from detonation, even though Mercruiser spec is 8 degrees BTDC. And then, he says he changes it as needed, about 1 degree at a time, until he gets the best performance.

One of the archived posts I read had a comment in it that started out with "Commit this to memory:" and then listed several symptoms that were most likely, in his opinion, related to timing first & foremost, and not necessarily a fuel issue, and one of those things was bogging/hesitation on acceleration.

I'll update with results.

 

[thompson80]

Re: Merc 3.0 carb cost?

Ethanol-free gas is available almost everywhere, look here: Ethanol-free gas stations in the U.S. and Canada Some marinas have it.

Closest place from that link to me is Des Moines Marina, about 7-8 miles, which was $3.69/gal a couple days ago. Next closest is the Narrows Marina in Tacoma (almost 20 miles): Chevron, at $4.64/gal. that same day!! Almost a dollar per gallon difference! Needless to say, I drove up to the Des Moines Marina with two 5 gallon jugs and walked those heavy buggers the 150 yards up to the truck, and drove home to top off the boat, even though I'm going to launch at the Narrows Marina on Monday. By comparison, the cheapest ethanol blend auto gas near me is probably Arco, currently around $3.13/gal. A fifty-six cents a gallon difference I don't mind paying for, but a $1.54/gal. difference, I do mind. That $99 carb mod would pay for itself pretty quickly at that premium.

Shows one dealer in Chelan, and NO place at any town surrounding Lake Washington EXCEPT Seattle, and the 3 Seattle dealers are all out on Salmon Bay in Ballard, which figures (home of the fishing fleet and several marinas in the Bay or nearby). It wouldn't be worth fighting the traffic to get out there unless you planned to boat nearby. So I guess I'm lucky that I have to drive "only" 8 miles to get ethanol-free gas, and it seems they're one of the cheaper dealers around. At least this week. You know how that game goes...

 

[thompson80]

Re: Merc 3.0 carb cost?

I was told i need a new carb for my 3.0 merc cruiser in/out. I was informed that it has already been rebuilt (new boat to me). The cost is $900 plus $200 for install, does this seem right? I thought it was a little high. Thanks for looking and any advise or answers i can get. Oh and it's a double barrell.John

To stay on-topic, one other thing I would relate from my visit to the carb shop today: I mentioned to the carb rep that I see brand new made-in-China Rochester 2GCs on eBay now for $285-$295. The carb guy said, unsurprisingly, "Stay away from them! They are junk! Bad castings!" etc. Said he had one guy bring one in, and gas was literally dripping out of the bottom of the bowl.