348 fuel pump rebuild

Hi Ian - I think what's being said here is that ethanol added to gasoline in the US does have oxygen in it. And if it separates from the gasoline due to a car sitting for a while, then nearly pure ethanol may be in touch with the fuel tank. PS - if Fat Billy Bob's reference is correct, they seem to be saying foam is good for either gas or alcohol, but not both. You pick one foam for gas and a different one for alcohol.

 

Yup - same here in Phoenix/Maricopa County.

 

Ian is fortunate that he might not have to deal with E10 we have now, for his area the foam might work, not in the US!

The upside is Ernie has reset the rubber time clock to zero by using the OEM parts, that should give about 5+(?) years of no troubles using the rubber at bare minimum IF the fuel remains constant.

With all of the fuel research I did this summer and fall, things are now starting to make sense now. We have been seeing the rubber issue for sometime now and it was Brian that first identified it was more common on cars that sat unused more than normal. Now understanding what the fuel is and does from my lab rat tests, much of this is explainable as I have seen it in graduated beakers full of fuel at the shop. Much of my initial research was limited to fuel hose but I have now gone way beyond that as this effects everything rubber in the fuel system. Frustration would have many looking at Ferrari thinking bad quality parts but that isnt the case and it isnt their problem. They build parts based on the fuels of the day and it is the fuel that has changed and is causing the issues and I suspect things will get worse before it gets any better. For this reason I have been working with engineers at a well known hose company having all of these parts remanufactured in compounds that will hold up to todays fuel and beyond. We know what compound works and what doesnt with todays fuel but if I am going through the cost and hassle of having molds made I want the new parts to stand up to the fuels I predict we will see years out from today. Think that the E10 is limited to 10% alcohol when it is pumped into the cars? Think again, I have tested much higher than that on a couple of occations in just the last few months and wonder what the future holds for us. Some say hogwash, the EPA mandates the levels...test for yourself. Things appear to have gotten much better as the price of crude dropped. In the last month I have tested a high of 9.9% but suspect my tests are no better than plus/minus 5%. Lets just say that if I used the 5% figure biased to the low side, we still had a problem on two tests conducted.

Ernie, seeing as you have yours all apart, inspect and photo the rubber sleeves in the plastic fill tube to the tank. I have been seeing failures in this area for the same reasons noted above. This is the one area where the 360's have an advantage, the late Motronic system self tests for any fuel system leaks on each drive cycle start up and will set a CEL if a system wide leak is detected, the earlier cars do not so we have to test for it manually.

There are a number of tests and procedures in this industry that are kept as hard earned proprietary secrets. I decided months back that this posed a very real danger due to fuel leaks and fire and decided this had to become public information that every owner was fully aware of. Inside the tank rubber problems are a PITA issue, fuel leaking outside is a serious safety hazard.

 

I got another victim willing to take his 550 apart. That means another get together. So when will we see your 348 join the other ferraris on my driveway?

 

You got to be kidding me! After the Tbelt are you going to rebuild your brakes next? Anyway, my buddy's NSX will probably not be out of my garage for another 2 months. You know the ernie gearbox thing. I'd be so anxious to get rolling again I'd have that engine built in a day and back in the car in a day.

 

Plugzit's got an extra space in his garage and a few lifts and dollies for you. We can have a Stoogefest and service your engine in a day!

 

Just about done now. The molds to do this are damned expensive! I had to do four to accommodate all the pump sizes and variations, the rubber mount pad and fuel filler neck variations. Surely not looking to be a profitable venture but at least we will have it available. Viton is only part of the answer to the problem.

Dave

 

I have a couple dozen pump assemblies on the shelf that were from street cars and the old challenge series cars running pump and race fuel and see no indication of any pending failures of the plastic. That's not to say I disagree with you, I do but the molding costs are so darn expensive I have to choose my battles these days with so many projects underway. If this was a Chevy and I knew I would sell a thousand, things would be different but when planning these out I can only take for granted that I will be the only one using them at my own shop and have to figure my payback based on this alone. Surely when I have these done they will be offered here and if there is any volume the price will obviously come down but these ultra small runs are hell when setup costs are involved, Birdman, Verell and others know this first hand. When issues of safety and fuel are at hand, no corners can be cut and perfection the first time around must be an absolute. Constant submersion in the fuel presents its own set of challenges with both the compounds used and the molding process but I have recognized pro's working on this so I have no concerns. I personally know only what I learned from my research when I found the fuel hoses failing and that is only enough to be dangerous, not helpful. There are 3 different size pumps used on the various models and I needed to adapt for all of these variations yet keep the costs reasonable so we can all afford to do the job with proper components that will last on all of the models affected by this problem. Nothing a boat load of money wouldnt speed up but I am getting them knocked off one by one. It was the efforts of Troy, Verell, Birdman, Stooge Crew and the likes that made me decide to take these on, it will be the only way we will all be able to afford to keep these cars running. Together as a group it is all doable.

I am underway having the fuel filler neck sleeves done at the same time but I see your fix to be so simple and effective that I am not so sure this doesnt present a better solution. There are those that will want the OEM plastic tube retained and for those I will have safe replacement sleeves in short order. I am not a big fan of the marine hose only because it is difficult to handle and properly clamp. As I am already underway with the thin walled tank cross over hoses for the older cars where I took the fuel retension spec's of the US Coast Guard and doubled them (Yes, I am a Chicken Shlt), I could easily make a fire resistant, bombproof replacement hose much the same as you did but utilizing the plyable nature of the silicone hose to assure easy clamping and handeling. If there is any interest in heading that direction I can have things like that done quickly and easily. I like what you did there and never felt too good about the plastic but I suspect it was used so in the event of an accident, the plastic accoirdian would stretch a great deal and not just pull off the tank as a rubber hose would thus allowing fuel to flow freely from the tank...... I just talked myself out of the rubber hose filler neck conversion business and will stick with the new compound sleeves already in process. I still like what you did regardless.

 

I must say ernie got off pretty good on his 348...the deteroration looks mild for a vehicle that old..
I have a pump assembly that came off a 97 355 and let me say that none of the rubber is recognizable except for a very small portion of the electical boot covers(they are mushy goo also but reatined some shape). Every bit of this rubber is nothing but black goo...totally dissolved and completely unrecognizable. The plastic fuel feed hoses are extremely brittle and the main feed hose was cracked. The main plastic container and basket are OK. The seals are gone also at inlet and return fittings.
Another problem is where does this dissolved crap go?? Well some was found in the fuel pump, fuel filter, fuel hoses and deposits found on the fuel rail and injectors. Evidently the fuel filter catches the big stuff but at the molecular level adds no protection. As long as the fuel flows and is warm maybe there is not much of a problem but when the fuel sits and cools in the fuel rails and injectors it comes out of the gas solution and begins to lay down some deposits.
This is a big problem on cars that are not driven very often and the fuel is not fresh. This car set for a few years so it will be at the extreme worse condition.
If you let your car sit and the fuel becomes unstable I can see some major problems in the fueling of your engine.
This crappy intank fuel rubber is not just a 355 problem and replacing with factory OEM new parts is just throwing good money at a problem that will reoccur in a few years and that time period can't be accurately determined because it will depend on the fuel composition, freshness of fuel, and use of vehicle. But no matter what why or how you can bet 4-5 years max in the absolute best scenerio.
Just wonder how these engines like burning rubber not at the rear wheels but in the combustion chamber...lol

I must add that Dave Helms is on top of this....I would expect nothing but the best from Dave's efforts. If I trusted anyone to come up with the best of the best for these cars it would be due to his love for the marque and a big bank account..lol