Today’s work started with the slow process of removing the fuel system on the engine.
One project that I’ve encountered, and to some degree I’ve encountered this all all old cars that have not had rubber lines replaced on a regular basis is that the clamps really distort the rubber and over time (in this case probably 41 years) the rubber hose changes and is often difficult to remove, with razor blades often need to be used to cut the line along the length to release the hold it has on the metal.
Fuel Pressure Regulator
Removing the lines from the fuel pressure regulator was one such problem. The clamps had distorted both lines enough that I really needed to resort to some major pulling. The key thing is that the line going to the tunnel needs to be removed because there’s a large nut that holds the regulator to the front tin. You can’t get it off without the line being off.
Eventually everything came off.
Fuel Delivery – Main Injectors
The fuel pressure regulator delivers fuel to the 1/2 fuel array and injectors.
It is almost humorous how many small hoses are on this system not to mention the number of clamps. On the 1/2 side alone there are 6 small clamps! These have been on here for a very long time so all were difficult to remove, some needing razor blade cutting.
Now I’m not saying it would be impossible to replace these lines with the engine in the car, and I’d imagine it would be pretty easy if everything was new and there was no corrosion and the hoses had not deformed or bonded to the barbs on the hard fuel lines. But I just can’t imagine trying to really do removal on such old stuff with my hands in the small space available.
The injectors are held in place by a plate that attached to the manifold itself, keeping it all from coming out. The injectors have a large outer o-ring seal that will not let them come out of the dual-o plate. There is one small inner o-ring seal towards the tip of the injector and this is what holds the injector into place in the manifold.
With the larger o-rings removed, the injectors slid out of the plate housing.
All of the metal items that hold the injectors in, and then hold the fuel rail splitter in place, and then ultimately mount to the the manifold itself are fairly corroded and will need to be sanded down and painted. I’d love to have my own blasting booth for such small pieces as I’ve love to take them down to bare metal but I’ll make do with restoring them to the best of what my garage allows.
All injectors came out fairly easy, but getting their rubber lines off the metal lines was difficult as the clamps really crushed and deformed the rubber.
With nothing to really compare them to, the injectors themselves just seem dirty but the inner o-rings on all seemed fine and tight in the manifold.
Fuel Delivery – 5th Injector – Cold Start Valve
On top of the throttle body/plenum is a type of 5th injector that is very different from the main cylinder injectors. This is called a Cold Start Valve and the primary purpose, based on info from the ECU, is to spray additional fuel when the temperatures are low. This fuel gets injected into the air mixture way before the heads.
The cold start valve is fed off the mail metal fuel line as it splits at above the alternator.
It is really noticeable how different this is from a standard fuel injector. I am going to have to create a custom gasket for this when it is reinstalled.
Fuel Delivery – Metal Lines
With the clamps and rubber lines all removed from the 5 injectors, the metal lines themselves came off.
It appears to be a steel line, not much different from the steel line that runs through the tin to delivery fuel to a rubber line to the carb in a Pre-1975 model Beetle. However, it has a split that feeds the cold start valve. All ends have small barbs to help lock the rubber in and the clamps then seal against these barbs.
There are 2 metal splitters at each head. Each of them has a metal mounting plate that is where the ring plate for the injectors attached and then ultimately it connects to the manifold itself.
Both are heavily corroded but I think they’ll all polish up fine. I don’t think I can paint these, or at least I cannot paint the surfaces where the rubber connectors. I’m thinking polishing these up the best I can then perhaps a couple coats of clear, keeping the barbed ends clean. The mounting plate will get fully sanded and painted some kind of silver or gray.
From the overall inspection of the parts, I cannot see anything really wrong with any of them, other than age and some corrosion.
However, the rubber fuel lines themselves should probably have been replaced 20 years ago or more frequently.
The fuel hose feeding the system at Cylinders 3/4 showed the worst degradation. I mean, this is an accident waiting to happen.
The culprit as to why the engine started spewing fuel last year was indeed the line between Cylinders 1/2 and the Fuel Pressure Regulator.
I still have no idea what this may have touched, but if you look closely (above) I think that it it had hit a hot surface it would have melted equally and instead is made up for small gouges through the rubber, then through the insulating high pressure lining. I’m thinking this was mice that cause this.
There’s just nothing up in this area that really is all that hot. I don’t think the intake manifolds get all that much heat from the heads. I suppose it is possibly, but this is just so different from the cracked rubber on other hoses that I think this was eaten through.
While extremely dirty, I think the inner smaller o-rings on the injectors themselves need replacing but this kind of grime is common on even non-FI cars.
Another part that differs from the Pre-1975 configuration is that the intake manifolds just just have a metal or fiber gasket. They have a spacer that adds more height, lifting the manifolds up higher and away from the hot head surface. This reduces the risk of the heat impacting the injectors which are literally right at the intake ports.
I am not sure of the material, but I don’t really think I need to replace these. I think cleaning them up and then reusing them will be fine. I’ll research it a bit more and see if I can find anything out on if they need to be treated like gaskets.
The next steps will be to clean all of the metal, paint what can be painted, and then get the injectors off to a specialized service that tests them and then cleaned them, installing new rubber lines on to them. There’s 2 services I’ve looked into but I haven’t decided yet on a vendor. It should run around $100-$150 to do this depending on if they can do the cold start valve as well. I’d like to have that tested and cleaned.
I think I need to bubble wrap the injectors, but everything is more or less ready to go once I choose the vendor and ship them all out.