Darn Mastercraft

eleeski

I love the MC wake. Unless it's the wake thrown when the boat is being towed in dead.
Kirk's 04 MC has fuel pump issues. The in tank hose burst. Replacement hoses never lasted long. Then the pump motor failed. I replaced that. When the new one failed again I gave up and bought a whole new fuel pump assembly. Three weeks and the new one failed. Horrible engineering.
The problem is twofold. First, the assembly is ridiculously complex (and expensive). Second, the hose doesn't work. For some reason the pump is 3/8 diameter and the check valve it attaches to is 5/16. Nobody makes submersible 5/16 fuel line. Regular fuel line softens and bursts quickly. 3/8 submersible line is very stiff and splits too easily. Plus it won't seal on the 5/16 check valve nipple. How can it get fixed?
The MC forum talks about this a lot. My 10MC hasn't had a problem - yet. But I have heard of new boats with problems. MC says they are stuck with the certification specifications and can't redesign. Bush/Obama's fault? Whatever it sucks.
Has anybody successfully fixed the problem in the field?
Eric

BraceMaker

Is this the Carter pump?

Here's a possible fuel line - 5/16" submersible.

http://www.frsport.com/Gates-27093-5-16--Submersible-Fuel-Hose-For-In-Tank-Lines-SAE-30R10_p_15937.html

eleeski

@Bracemaker Good lead! This may be a new product? I think I ordered the 3/8 submersible from them a while back but the 5/16 is the critical item. Thanks.
Now hopefully Kirk didn't destroy the unit with the broken line and I can repair it.
Eric

BraceMaker

My first instinct was Tygon fuel line - this saved my hide a time or two on MC stuff, but from your description this line is either siphoned or pressured, tygon collapses like crazy, and is only pressure rated to about 25-40 psi depending on the diameter. But it is SUPER fuel/chem resistant stuff. And super flexible, hence I've used it in situations where other lines were getting soft due to exposure (like Motorcycle tanks)

If it is the carter pump I think there is a 90$ autozone replacement, like you I'd have to search TMC.

BraceMaker

http://www.mastercraft.com/teamtalk/showthread.php?t=25783

RichardDoane

@eleeski - Fuel injection grade flexible fuel line is submersible, we buy it from AC Delco on a 25' roll, let me know how much you need and I'll send you a chunk

eleeski

So I pull the submersible hose out of my parts box to check the numbers (J30R10) and notice that it's 5/16. An ok fit on the pump motor but loose on the check valve. I guess the size they don't make is 1/4 submersible. Unless @Richarddoane has 1/4"J30R10 that he can send me.
@Bracemaker The original fuel line may have been Tygon. It looks like 1/4 stretched to fit the pump motor. It split at the bend. The newer pump assembly has Tygon(?) That is corrugated to bend easier. The ends seemed molded to different sizes. I was unable to find this part for sale. The new one split or chafed a hole in it. The "new" fuel pump assembly may have spent too much time on the shelf making the line stiff and brittle.
I was able to find corrugated 3/8 ( or is it 5/16?) that fit the pump motor ok (it did need heat to go on). Now I need an adapter to the 1/4 check valve. Why didn't they make all the hose ends compatible? And why does the thing need to move and float necessitating a flexible hose? Crappy design.
The boat is down again. And my wallet is nervous.
Eric

eleeski

Sorry, I didn't find the part number for the fuel pump motor. They are readily available. My replacement failed quickly because of contamination. A chunk of red plastic (from a gas can?) was jamming the motor and burned it out. I'm not sure how it got past the filters - crappy design.
Eric

Jody_Seal

you could all way's remove the in tank pump system and install a PCM FCC fuel delivery system on it!

eleeski

@Jody_Seal Could I really? If the fancy hose from the tank to the engine is the same size and the PCM assembly is the same or smaller I'd try it. Hopefully it's not the same item rebranded. I've heard Malibu uses the same part?
Eric

Jody_Seal

@eleeski. The high pressure fittings are common between the indmar and the PCM. It would take a little bit of engineering and maybe some light fab work but yes it is a very viable solution for the in tank fuel delivery problems of the Mastercraft.
I have some pull off FCC components you would need to buy new fuel pumps (2), I have all the hoses, brackets and FCC hardware to make one work.

BraceMaker

Does anyone know a real answer on this?

Does the fuel pump/regulator have to be integral and mounted on the tank? That being, is there a requirement that excess fuel pressure return direct to tank and does not travel through fuel line to a regulator at the engine under "full" pressure?

Products such as retrofit fuel systems for adding fuel injection to carbed cars-
http://www.tanksinc.com/index.cfm/page/ptype=product/product_id=227/category_id=61/home_id=-1/mode=prod/prd227.htm

Could possibly be made to work - but all will have the regulator up by the engine and a return line. Sounds like the CC version does not have an "in tank" regulator?

Waternut

Any chance you could run a hard line in there? Even if you ran a 1" section at each end with hose clamps to splice it, it would reduce your chances of kinking and it would be harder to fall off since it's pinned. I don't know though since I don't have one but looking at the pictures on the mastercraft site, it doesn't look like the hose needs to be flexible. Just looks easier to install that way.

DW

Not for the fainthearted, but one solution if you end up totally frustrated would be one of the GM automotive in tank pumps. Many of them have no rubber lines, the fuel inlet to the pump is the screen on the pump, the outlet hose is a durable plastic hose so that would connect up to the fuel tank flange. You would have to make a custom tank attachment flange but the outer housings for applications such as the Silverado/S10/etc. all accept a pretty wide range of depths using one housing. They have three hose attachments - pressure feed line, return line, vent line that goes to the charcoal canister. If you end up doing this, make sure you get a true AC Delco pump and not one of the Airtex units that will fail in 6 months.

eleeski

@Jody_Seal got me the latest MC fuel pump module. Vast improvement from an engineering perspective. Dual pump motors for redundancy. 5/16 by 5/16 lines to the tee, 1/4 by 1/4 from the tee to the regulator/check valve. Filters that might actually filter and a design that might take advantage of the tank's full capacity. Better! But I still need a source for 1/4 submersible fuel hose to be able to completely service the pump.

Thanks MC and Jody.

Eric