All, Following on from my recent issues with the bus cutting out/juddering at low revs I have decided to give the fuel system a good going over. I would appreciate any comments and suggestions on my plan of action. I have a type 4 2.0l engine with twin ICT34's which until fairly recently were running well. They were installed and set up on a rolling road 3-4 years ago and we had no probs. I did suffer with fuel overflow into the carbs (which contaminated the case) when the bus was parked up so installed a one way fuel vale which did sold the problem but I think it has had its day and is leaky. I changed the oil when all that occurred of course. Pretty sure the needle valves are ok as I had the tops off of the carbs and revved it up on the drive. fuel was delivered but when the throttle was released I could not see any fuel continuing to come through the valves. Plan is to fit a fuel filter below the tank and before the fuel pump and then fit a malpassi petrol king fuel pressure regulator (without the bowl) downstream of the pump. first question - where is the best place to mount this. Second question is how do I confirm the fuel pressure itself. I read on the wayoutwestie website these carbs need around 2.5psi to run right but I have no gauge. Do I need to get one and install downstream of the regulator? I then got hold of x2 F6 emulsion tubes and service kits for the Webers - the plan is to take them out, give them a good clean, install the tubes and new needle valves. I'll remember t count the turns on the mixture screws. And then reassemble. I also bought all new fuel line and clamps. I've not done this before so know I'll need to take lots of pictures, write notes etc. The two things that I really need to get my head around is mounting of the regulator and pressure gauge.
If it filled the oil with fuel , its just as well you are chnging the needle valves. It doesnt do it when you are looking but 12 hours later it just seeps through. It doesnt need pressure from the fuel pump, just the tiny static head from the fuel tank. It has to be really bad to make any difference to a running engine. A cause of the needle valve wear worsening could well be vibration caused by a poorly running engine caused by needle valve wear... A cheaper solution than a pressure regulator may be either a (also fire retarding) solenoid shutoff valve near the tank, or a check valve in the feed from the pump- they need a bit of pressure to pop open.. If running a stock fuel pump the pressure is already in the ballpark. If you do decide to buy a pressure gauge , buy one with a glass face.. petrol "frosts" the plastic faces of cheap gauges if it gets on them.
They need mounting somewhere that engine vibrations won't effect. Mine was on a bracket clamped to the bit of metal between leisure battery and under spare wheel well. Don't mount it on the fan housing - which is where mine currently is!
You could dangle your Malpassi from the spare wheel well. Yes, you will need a pressure gauge downstream, but I wouldn't leave it permanently connected. Just another potential source of leaks. Just make up a couple of lengths of fuel hose with a "T" in the middle.
Thanks - good advice. My only issue with the regulator being on the spare wheel well is that the fuel line enters from the right hand side of the firewall. Means it's going to have to go all the way over to the left only to come back again. Not a big issue of course but I will ponder. Just waiting for a fine day to crack on with this. Going to check the oil first as well as I suspect its going to be smelly and need changing!
I've only ever seen the fuel line entering on the left as you look in to the engine bay, interesting that yours is different, though could be changed to make it easier.
German built bus for the Australian market. It actually has no M code plate either. I looked it up and apparently this is a thing.
Well here's a turn up. Was under the van surveying how i can get a new fuel hose from the fuel pump up tot he engine bay (current one is not long enough to where eI plan on mounting my fuel regulator) and what do I find? Looks like a blanking plate on my fuel pump and what I thought was a fuel filter is in fact an electric fuel pump (which explains why the boxy thing that is under there has electrics to it! Not 100% happy about this...
Can someone confirm or deny what I think I've just found out? Is it impossible to remove the firewall from a bus with a type 4 engine in it without dropping the engine. I've removed all of the firewall screws and the firewall is definitely loose but it looks like its fouling at the bottom on the rear engine tin (the firewall is behind the tin). Because of this I cannot lever it out from the bottom and of course the top is tucked up under a lip as well. I wanted to mount my fuel pressure regulator on the firewall and don't want to be blind drilling holes. Nor do i want it secure with self tappers - proper nuts/bolts/washers is what I want.
Was aware of those two "hidden" screws. Someones been in there before me as they are both absent. Still can't see how to get it out though - am staring at it thinking "there has to be a way" - without bending tinware...
Can’t remember having an issue removing mine. I have mounted the fuel pump onto a plate and the plate to the firewall with 4 x self tappers, seems solid to me. Use a small battery drill & 3mm bit to drill the firewall. Light pressure so you know when it’s breaking through. Then poke a small screwdriver through to feel the distance to the tank. Mine was a good couple of inches away from the firewall.
Thanks for this. Going to go for this approach. The PO drilled the firewall to mount the holders for the extinguisher so I did consider it.
Update. Fuel pressure system is mounted but at this time not plumbed in. I thought I'd just check everything was still ok before I change over. The reason being that I will have to run a new fuel line from the electric pump up through the firewall to reach the regulator (current one will be too short). Anyhoo, reconnects everything and she fired pu first time - only problem though is it still cuts out at idle/low revs - if I give it some throttle its fine but just drops out when idling. I have electronic ignition, electric pump and twin ICT 34's on there. I wondered if this is some crud in the carbs and I need to man up and set to work cleaning and servicing the carbs. I cannot think what else it can be. I know I need to get the regulator fitted long term to prevent over pressure on the carbs but I right now it just won't run at low revs....
I would set about giving the carbs a good clean & blow through first. Idle jets & passages easily block up with a bit of crud in the system. Make a note of how many turns out the mixture screws are before you strip them down. Make sure the float level is set correctly & the butterflies are both set the same. Other common problem is an air leak. Check the servo hose & balance pipe also manifold and carb base gaskets can be suspect.
thanks - going to check all the pipes and then go from there. Have the kits and tools, watched a few vids so going to go for it.
Well I popped my cherry. First carb is off the bus, in pieces and in a box in my garage. Spot of lunch then carb cleaner, a brush, air duster and lots of cleaning. Was pretty easy to take apart - took lots of pics and of course have another one to refer to if I get stuck. Counted the turns on the mixture screw and made a note as well. Was well cruddy both inside and out. Should I use all of the kit when replacing it - definitely going to use the new needle valve and seat and have the way out westie guides for setting the floats. Any other tips?
