Engine warm-up Exhaust flap

[JimD]

Hi,
I want to check that the exhaust shutter is properly open. From the engine manual illustrations the lever is moved by a diaphragm and rod. Could anyone tell me whether the rod pushes or pulls to open the flap? Otherwise I think I'll need to remove the unit so I can see through the pipe. At the moment the screw holding the cover on is sprayed with WD-40, and hopefully I'll be able to get it open and see whether it can move tomorrow!

Thanks for any advice.

[mister munkey]

Do you mean the valve that works off the switch in the twin batteried winter pack Bongos?

[Driver+Passengers]

I'm pretty sure that's what he means... 1355C?

[JimD]

That's right. Item 13-540 in that diagram.

Ah well, it was stuck, but in the right position (the rod was 'pushed' out). By working the valve backwards and forwards with a socket on the end of the shaft, I freed it, then found that if the switch was on the rod was pulled. It's working now, in case I accidentally use the switch, but I need to look somewhere else for the reason fuel consumption is so high (18mpg last tank)

[Driver+Passengers]

I'm surprised that I've not been able to find an exploded diagram for that part. Let us know what you find out...

[JimD]

I'm surprised that I've not been able to find an exploded diagram for that part. Let us know what you find out...

There are diagrams in the engine manual. The rod pushes and pulls a crank on a shaft carrying a butterfly valve. There are two bolts sticking up that can be adjusted as stops to set the extremes. The problem I had was that I couldn't tell which position of the crank was open, and which was shut.

[Driver+Passengers]

JimD - have you or are you going to blank your EGR? Or are you just wanting to check the valve is open and leave it at that?

Related questions:

- is there any benefit to keeping the exhaust flap in place if the EGR is blanked off? By that, I mean using the warmup switch...
- the warmup switch also effects a fast idle. With EGR (and potentially exhaust flap) removed, is the fast idle a good idea on its own in cold weather?

[Driver+Passengers]

You could try switching the warm-up on and note new position of rod - that should tell you, no?

I'm going to be replacing the front exhaust pipe in a few days, so unless you've worked it out already, I should be able to let you know what it's doing inside.

[Driver+Passengers]

As you look from the actuator towards the exhaust valve (ie from the outside of the van towards the middle), the visible portion of the shaft rotates clockwise to close the flap, anticlockwise to open it.

Don't know if that helps you.

[Driver+Passengers]

That's right. Item 13-540 in that diagram.

Ah well, it was stuck, but in the right position (the rod was 'pushed' out). By working the valve backwards and forwards with a socket on the end of the shaft, I freed it, then found that if the switch was on the rod was pulled. It's working now, in case I accidentally use the switch, but I need to look somewhere else for the reason fuel consumption is so high (18mpg last tank)

Just saw this edit - sorry, I've been posting useless comments since!

18mpg - ouch!

Have you checked your brakes aren't binding? Plan a route where you can drive for >10 minutes without using the brakes and coast to a stop in some large layby or something. Then get out and feel all the discs. Fuel filter (inc. banjo filter), tyre pressures not silly low, fuel line leaks... hope you find the cause and start saving some money on fuel!

[JimD]

Hi D+P, thanks for the suggestions.
Unfortunately I wasn't following the thread properly after my last post...

Anyway, I took my tyre pressures up to 40psi after the last fill-up, and the last 190 miles was two 60-mile runs plus a little local running, being light-footed. That turned in 22mpg.

I've just blanked the EGR, and it's running several degrees warmer. I'll have to watch out when the warmer weather rolls around again. Not been blanked long enough to get fuel consumption yet.

I also have a bottle of Slick 50 to add when I get around to removing some oil to make room for it.

I'll check for the brakes binding at some point.

Thinking of getting a K&R air filter too.

[Northern Bongolow]

are you 4 wdrive ?

[Alacrity]

I would NOT use Slick 50 in your engine, I have experience of this causing MAJOR oil pressure issues after it has been used. Do a search for Slick 50 on here & you should get some answers.

I have myself had/got excessive fuel consumption myself (4wd diesel auto) & I had brake binding issues which turned out to be servo pushrod over adjusted, you couldn't roll the beast on flat ground on your own at all. OK now. Unbelievably the consumption issues persisted after sorting the brakes, I couldn't believe it! I think I may have sorted now but I have thought that on several occasions & have announced it here & had to come back with my tail between my legs when it was till the same.

The latest is this, the exhaust broke after the front silencer just before the flange for the rear silencer. Instead of it being noisier all I could hear was a really loud hissing when I put my foot down, something I have had before at work with blocked exhausts. Anyway that particular journey took me from Eastbourne to Southampton & back, towing a small boat & she used a whole tankful to do the journey. The following weekend, having replaced the exhaust section with a new one, I drove from Eastbourne to Chichester & back towing the same boat. Now I know that is a slightly shorter journey but I only used a fraction over half a tank of fuel. I wouldn't think the bit from Chi to Soton would have used the other half of the tank so I may have cracked. Next longish journey I do I will do a proper check & see. Finger crossed.