[barnesy]

Hey all i was checking for vacuum leaks on my patrol after dawes install accidently snapped centre fitting off vacuum cannister.

Is it possible to bypass this unit? as the later models dont run one?

Anyone had to fix this problem before, or should i chase up a replacement?

Cheers
Barnesy

 

[Chaz]

I worked on a car a few months ago that had low boost. It turned out to be a crack in the canister that was on the engine, so we bypassed it. Everything seemed to work ok after and his boost was back where it should have been. I doubt that it will cause any issues because as you said, the later models haven’t got that one fitted.

 

[geeyoutoo]

I worked on a car a few months ago that had low boost. It turned out to be a crack in the canister that was on the engine, so we bypassed it. Everything seemed to work ok after and his boost was back where it should have been. I doubt that it will cause any issues because as you said, the later models haven’t got that one fitted.

Hi Chaz,
Often wondered about this myself, having worked with small high efficiency vacuum pumps for many years on high speed packaging machinery I fully understand the logic behind surge/servo tank but one would think the reaction in this case would be instant and there is no spent vacuum as such, just a degree of ramp up and down, might trial it for a few days myself just to see any effects.

Didn't they drop the surge tank after 2003?

 

[Chaz]

Hi Chaz,
Often wondered about this myself, having worked with small high efficiency vacuum pumps for many years on high speed packaging machinery I fully understand the logic behind surge/servo tank but one would think the reaction in this case would be instant and there is no spent vacuum as such, just a degree of ramp up and down, might trial it for a few days myself just to see any effects.

Didn't they drop the surge tank after 2003?

Hey mate,

I have an October 2002 build and it doesn't have the tank. I wondered how this would affect the manual boost controllers that we fit also, but it doesn't seem to make any obvious differences.

Also, I think the tank is in a bad place where it gets a lot of heat and vibration, so it’s another item that is doomed to fail, but removing it seems to be the cheaper option.

 

[barnesy]

ok guys ill reconect everything this morning and see how it goes, i have another unit ready to pick up this morning just in case

 

[barnesy]

everything reconnected test drove car seems to be no difference between having 1 and not, mind you i only done 10 kms

 

[harry6781]

Mine has been bypassed for over a year now with no difference whatsoever. I have driven around 20,000Km

 

[geeyoutoo]

Hey mate,

I have an October 2002 build and it doesn't have the tank. I wondered how this would affect the manual boost controllers that we fit also, but it doesn't seem to make any obvious differences.

Also, I think the tank is in a bad place where it gets a lot of heat and vibration, so it’s another item that is doomed to fail, but removing it seems to be the cheaper option.

Good feedback Chaz and Harry, I have always subscribed to the theory that if the manufacturer put something on a vehicle they did it for a good reason (they want to save a buck as much as anyone), but in this case it would appear to be just a theoretical advantage they foresaw and eventually removed.

Mine actually rattles in its bracket as the rubber mounting has deteriorated. Know what to do now.

 

[harry6781]

There is one downfall that I have noticed. but it might not be caused by the removal of the vacuum canister. My clutch becomes extremely hard to push in after going down long, steep hills using the engine for braking. I'm thinking that there isn't enough vacuum or maybe there is a one way valve in the canister. rev the engine a bit and my clutch is back to normal. This has only happened twice to me since the removal of this.

 

[02Troll]

Mine has the vacuum canister (cylinder domed on bottom) on the passenger side mounted between the ABS and the coolant refill tank, I think it would be important to keep it for your brake & clutch boosters, to provide an adequate supply of vacuum to operate properly and also to allow some operation of these two when the engine is shut down.

 

[geeyoutoo]

Mine has the vacuum canister (cylinder domed on bottom) on the passenger side mounted between the ABS and the coolant refill tank, I think it would be important to keep it for your brake & clutch boosters, to provide an adequate supply of vacuum to operate properly and also to allow some operation of these two when the engine is shut down.

Hi 02Troll, We're actually discussing a different canister, which is mounted under the IC cover, your talking about the brake booster surge tank, which is absolutely necessary.

 

[02Troll]

Thanks for that,
It seemed a bit obvious, but I thought I would post a comment just in case others out there were misreading the information.
I have seen the other one in pictures and wondered what it was, mine doesn't have it, Oct 02 build.

 

[geeyoutoo]

Thanks for that,
It seemed a bit obvious, but I thought I would post a comment just in case others out there were misreading the information.
I have seen the other one in pictures and wondered what it was, mine doesn't have it, Oct 02 build.

Mines an Oct 2000 build, Barnsey's is similar vintage to mine and Chaz's is the same as yours and he doesn't have it either, so somewhere in the middle it was dropped.

 

[barnesy]

Yeah im oct 2000 also, i cant tell any difference i done 115km today with no problems at all, i thinks its safe to say its not needed

Thanks for the imput guys

 

[geeyoutoo]

Yeah im oct 2000 also, i cant tell any difference i done 115km today with no problems at all, i thinks its safe to say its not needed

Thanks for the imput guys

Hi Barnsey,

I'll also be trialing mine for a while so we can compare results, the question was a very worthwhile exercise.

 

[GU Bundy]

Hi Barnsey,

I'll also be trialing mine for a while so we can compare results, the question was a very worthwhile exercise.

Hi Geeyoutoo, mine is a july 2000 and I will disconnet mine tommorrow and connect the 2 hoses together and see if anyhting different hapenss and let you guys know if i find anything too.
Have been hanging out to remove it, but was not sure until now. had to turn mine around as it hit the CC intercooler.

 

[GU Bundy]

1000km and test results are in

OK! Results are in at my end.

Removed the 2 vacuum hoses from the canister and joint them together. I have done just over 1000km and have noticed no difference what so ever.

If anything I think I picked up some vacuum as the canister had a micro leak.

That said I did notice an over-boost limp mode on two occasions almost immediately within the gear shift between 3rd & 4th, but suspect this was purely coincidental as I have been trying to find the sweat spot between boost on the Dawes and spool up rate from my needle valve and every now and again it happens--- So I don't think they are linked.

Looking like a great solution with no noticeable impact other than saving a few bob on new canisters, making room next to my CC intercooler, and no bloody rattle.