OMC V8 carburetor flooding

[whitesig]

OMC V8 175 HP, 1978<br /><br />I had my carb rebuilt because it would not accelerate over idle. The boat ran fine for about 2 hours. After the two hours it would bog down when I tried to accelerate. <br /><br />Therefore, I took the carb back to the shop and they blew out the carbureter and replaced the gaskets. They also said a pin on my float was broke and they fixed that. During the first test run it ran great for about 30 minutes. I took the boat out an hour later and noticed it starting bogging down when I went to full throttle. I checked the carbureter on the way in and noticed it was leaking fuel. I took the boat out again and it bogged down at half throttle and was again leaking fuel. By the end of the day it would only proceed at idle speed.<br /><br />I called the carb shop and they said to bring the carbureter back into them.<br /><br />Any ideas?

 

[Bondo]

Re: OMC V8 carburetor flooding

Replace the Carb........<br />Is it a 2bbl or 4 ????<br /><br />Rebuilds are Sometimes a 50/50 Roll of the Dice.....<br />Carbs corrode,+ Rebuilds just Don't address the Issues....

 

[whitesig]

Re: OMC V8 carburetor flooding

It is a two barrel. According to my Service Manual it is a Ford D3JL-9510-S

 

[Boomyal]

Re: OMC V8 carburetor flooding

It's probably a Holley 2 bbl. Sounds like you have a float problem again. The gas you smell might be from the float bowl 'j' tubes dumping the excess back down the venturis. Don't run it till you get it fixed. It could wash the cylinder walls and contaminate the oil.

 

[Bondo]

Re: OMC V8 carburetor flooding

Could be.....<br />My resourses say the Holley was on the 1975/77s,<br />And the Rochester on the 1978/81s.......

 

[whitesig]

Re: OMC V8 carburetor flooding

I believe it is a Holley. The service manual says the 120, 140, 165, and 225 HP used Rochester and the 175 and 190 HP used the Ford D3JL-9510-S. The manual doesn't mention Holley, but it looks like a Holley.

 

[BRIAN03]

Re: OMC V8 carburetor flooding

If there has been water thru it, or sat of any length of time(its junk). Replace it. Dont waste your money on a rebuild either. Buy a new marine carb. You will save alot of time and frustration. We have been thru the same thing with the local carb shop. Its not all(carb shop) there fault. Carbs have a life cycle. Our shop policy is if it over ten years its beat buy a new one. If it is a Holley and had water thru of any kind its Junk. Give (carb) it the float test. Bring the carb to a large source of water drop the carb in (depth must be aleast 10 feet) and if it FLOATS (its good) if it sinks its BAD.

 

[bomar76]

Re: OMC V8 carburetor flooding

Give (carb) it the float test. Bring the carb to a large source of water drop the carb in (depth must be aleast 10 feet) and if it FLOATS (its good) if it sinks its BAD.

LOL <br />I like that test....<br />

 

[rodbolt]

Re: OMC V8 carburetor flooding

hello<br /> about the only reason a 2bbl holley or rochester will leak is due to incorrect float hieght or bad/dirty needle valves. sounds like a careful inspection of the flaot and float pin should have been done the first time. also a float wieght test or I just replace them with a new one and dont sweat it. 2bbl holleys and rochesters as well as the 2bbl motorcrafts are simple carbs. not much can go wrong other than normal wear. now water corrosion is different. if I open one up that is all white inside I use the water test mentioned above .<br /> good luck and keep posting<br /> PS anymore with shop labor rates so high its almost always more cost effective to buy another carb.

 

[Yepblaze]

Re: OMC V8 carburetor flooding

Perhaps you have water in the tank and it takes about thirty minutes of running and sloshing around till enough gets in the bowl(s) to start entering the jets. That along with any rust or debris (if in the system and left unfilterd) will foul the needle seat causing flooding to occur.

 

[Walt T]

Re: OMC V8 carburetor flooding

I have never ever thrown away a caburetor. I have yet to meet one that couldnt be made to work properly provided one follows the specifications that come with it.<br />If it's broken, that's one thing. If it doesnt work right, take it back and they should repair it at no charge. <br />The problem is a lot of techs don't set them up properly, and use old parts like floats.

 

[wheels4]

Re: OMC V8 carburetor flooding

90% of carbs that are junked are not junk.I would love to have all the junk that has been thrown away,I would be a rich man.

 

[BRIAN03]

Re: OMC V8 carburetor flooding

Salt water and a Holley dont mix. I make my living on billable time. I'm sure I could take alot of time making something work. Is the customer going to pay for all that time. We charge 1 hr. diag time and 1 hr. to install. that it. Salt water gets thru an aluminum carb and will deteriorate the insides the metering blocks,float bowls and main body. You cant fix that. I've seen holes thru them. Maybe in fresh water they will last forever. Not on the coast. Its like outboards. You cant go to an inland lake and outboards last forever. On the coast they are all used up in 10 years. Salt water kills every thing it touches. I will correct my self If the boat is used in saltwater replace the carb. with a new one. Maybe you should open a carb shop you could make a killing if we are all wrong. Sierra got in the carb. rebuilding business and had a return rate of 25%. I sure the largest marine aftermarket company that owns the whole aftermarket business doesnt know anything about carbs. either. I dont throw out the old carbs. I keep them in a big box under the bench to show customers.

 

[wheels4]

Re: OMC V8 carburetor flooding

Youre right I stand corrected.Every carb that gets replaced is junk.

 

[BRIAN03]

Re: OMC V8 carburetor flooding

Not all carbs that get replaced aren't Junk. Its a matter of time verses money and what is the best for the customer over time. If the carb was on my street car I would take the time to rebuild it. If its a customer who is a DR. and wants his stuff perfect I can't take a chance of having a problem rebuilding his older carb. Every gallon of fuel the engine burns air is replaced in his fuel tank. In that air is salt mist over years it ends up in the bottom of his fuel tank and that salt is injested back thru his carb. On all repowers we vacuum the bottom of the fuel tank and filter the fuel. I have never seen a fuel tank used a few years. That didnt have somthing in the bottom of the tank.

 

[Walt T]

Re: OMC V8 carburetor flooding

All good points. Good thing ya'll wear hats. I am a fresh water weenie so I forget about the perils of salt water.

 

[whitesig]

Re: OMC V8 carburetor flooding

I'm taking the carb back to the shop. They said they will try again at no charge. Any advice on what they may try different?

 

[Squirterguy]

Re: OMC V8 carburetor flooding

Sure seems like floats are either sticking down, sinking, or needle / seat assembleys are not sealing correctly. I have been running a Holley, admittedly different from your conditions -- 4-barrell, fresh water, brutally large engine, since new on the boat in 1978. Was rebuilt in 1990 changing only gaskets, needle/seat assys, and cleaning. It runs as well as it did in 1978, which is "blisteringly fast". Perhaps you can corrode certain parts into trash, but since most of a carbs job is to be a tank, holding fuel, waiting to be metered through the jets/needles, a bit of pitting from corrosion in places other than mixture needles and jets rarely has any effect. All the important metering parts I have ever seen in carbs are brass or Stainless Steel anyhow.

 

[fireship1]

Re: OMC V8 carburetor flooding

Hello, Sounds like Jetaaron has a good point. Floats are generally inspected visually, and if all LOOKS good they reuse the part. However just because the float looks OK on the outside that don't make it so! The float might have a pinhole or a leaky joint (some are made in two parts and soldered together) and be taking on liquid. This would defiantly cause you to flood out and not run right. The other thing that crossed my mind was did anyone put any additives in the fuel tank (gas line antifreeze, water absorber) that had a large amount of alcohol in them? This would cause the rubber parts to swell and not seal properly. The accelerator pump and needle/seat assembly would be two things that might get damaged from excessive alcohol. Just a thought! Hope this might help!