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MG MGF Technical - INDUCTION WARNING

While out driving in the rainy Northumbrian hills on Sunday my MG with a viper induction kit encountered a flooded road. The result was I first thought a damp engine that cut out, what actually happened was the induction pipe filled the filter,throttle body,inlet manifold and 2 cylinders with water locking the engine.Thanks to the speedy (not) RAC 4 hours later I was home stripping the plugs out and draining the fish out of the cylinders.Fearing the worst turned the ignition key and P323 XJR started first time, with a little steam from the exhaust. Who said the VVC was a soft engine? Following this near disaster the air intake is now located in the original side vent, not low down as per instructions.Just thought you might all like to check the height of your intake pipes, especially if you have the lowering knuckles fitted.
Terry

Jesus you were lucky!!
Will Munns

Will, not that lucky you should have heard the language from the Mrs when I asked her to jump out and push! Yep very lucky I was expecting bent rods etc and sods law I had just spent £2000 on a fancy cyl head,fortunately with one of Mike's uprated cyl gaskets fitted!
Terry

With my airbox mod, I routed the intake to the nearside vent for precisely this reason... but after spotting a deep flood on an approach road to the North Circular, decided that it would still be better to do a U-turn and find another way!

Hydraulic lock of the engine = bottom end damage and ruined bearings/big ends and possibly also bent con-rods. Basically, very very expensive!!!

Glad to hear you got away with it Terry!
Rob Bell

Some of the roads round here alongside the River Severn flood regularly. Like right now with all that rain trickling down from Snowdonia's Mountains ....DOH! In fact BBC Radio 5 Live just mentioned Maisemore and Sandhurst with water rising so watch out. Some years ago, at Maisemore, I chanced my luck in the old Montego ( I have a spare ...!) to avoid a ten mile no guarantee of getting through detour by carefully driving through those Maisemore floods. Water just below axle height on the higher part of the road camber. The old car sailed through (literally and with a bow wave) and did not miss a beat. A BMW tried to follow me but suffered severe water lock with a ruined engine. I spotted several stranded cars as I emerged from the flood. Spectators who had gathered to watch the "fun' cheered and applauded .... some days things do go your way ..:O) but NOT always so be careful .. :-(

IIRC, all Montegos have a highish Air Intake just below the bonnet line at the front well above axle height flood levels. Even so, when trying to negotiate such floods, keep to a speed which DOES NOT put that bow wave of water above the Air Intake ... to do so is to invite trouble. Get to know where your air intake is on your car and drive through floods with that in mind .... Those driver's, and there are many, that need to ask where and what the air intake looks like should not attempt driving through floods ... :O))))
John McFeely

If you have a K&N 57i kit fitted, then you are laughing - the air intake is at the level of the door handles!!! LOL
Rob Bell

Yes but dont drive too fast Rob or you might just force water up the cold ram-air pipes and spray the filter.

A bit like a washing up machine:-)

Ted
Ted Newman

>>Yes but dont drive too fast Rob or you might just force water up the cold ram-air pipes and spray the filter.<<

Drive THAT fast Ted, and you're likely to drown in the bow wave in an F!!! ROFL!

You'd need the 007 'The Spy who loved me' Esprit conversion to get away with that... Hmm... One wonders where the air intake was on that car ;o)
Rob Bell

>>If you have a K&N 57i kit fitted, then you are laughing - the air intake is at the level of the door handles!!!<<

That'll be yet another good reason to fit a K&N then!

Jim
Jim

My ITG maxogen airbox is fitted to the side air intake for the reason of floods as it would give that bit more room when driving through floods.

I am not sure what the instructions say for fitting the pipe but Techspeed fit the pipe the same place on all cars.

Glad to hear that it looks like you got away with it Terry.

Tom
Tom Randell

This has always been my concern with closed air filter systems. The MKII Astra GTE had a similar problem when lots of water came in the bonnet vents but they revised it after having to replace several engines.
T.E.D.

Remember the original standard filter arrangement is a closed system, and the intake is about level in height with the side air grill, so as long as any new closed system does not take in air lower than the side air grill then it should be no worse than the standard arrangement!.
Jason H
Jason H

ITG Maxogen instructions say to mount the air intake pointing downwards underneath the car. This is because the 100mm diameter pipe wont fit past the subframe to get to the side air intake (it is non-compressable).

This is something i have been very worried about since it was fitted and following Rob's success with his DIY air box mod i moved my intake pipe a couple of weeks ago. In the case of the maxogen you need to cable tie it to the subframe as it will NOT go past it directly to the side intake - effectively it now draws air from the wheelarch.

SF
Scarlet Fever

I'm with Ted on this one.

I was up at St Andrews a couple of weeks ago, and on the way back the road was flooded. Besides from having water coming in the doors, I thought about the air intake.

So this begs the question. What's the height of the air intake for the standard 'F' intake system?

Cheers,

Leigh
L Reid

The standard *F* (as opposed to TF) has an induction hose from the resonator that goes down the back of the engine and its opening is level with the sump (approx).

Much lower than the K&N!

Ted
Ted

Terry, you were very lucky in deed after seeing the damage my father-in-law did to a citroen zx a couple of years ago, whenever we have some serious rain here I leave the 'f' in the garage and wind my way to work on particularly flood friendly roads in my freelander.

Hope your luck stays with you

Mike W
Mike Wainwright

>> The standard *F* (as opposed to TF) has an induction hose from the resonator that goes down the back of the engine and its opening is level with the sump (approx). <<

Hmmmm, are you sure Ted?

I ask because i have fitted a number of various air filters to a number of different Fs and they all had thier air intake pipe cable tied to the partition wall between the boot and the engine compartment, about ½ way up. This places it around 2 feet up from ground level (depending on ride height), quite a way above the sump.

Air intake route:

Air enters intake pipe, location as above, pipe runs horizontally around the rear left of the engine bay (first 90 degrees - under the MEMS) before entering the top of the resonance box. Air exits the resonance box at low level and turns through 90 degrees three times before entering the bottom of the filter box. After traveeling upwards, negotiating the filter medium it turns through yet another 90 degrees exiting the filter box at high level into the concertina-like pipe where it is discharged into the throttle body.

I do agree that the K+N air intake is higher still however, although the intake pipes are under the car, if installed correctly there should be a 4" gap between the higher ends and the filter itself. This means that the place that the engine draws air is the actual filter and not the pipes (they only supply cool air to this region), meaning that a K+N equipped F draws air from the top of the engine bay.

SF
SF

Andy

I can only speak for mine BUT yes there is a brown(ish) flexi pipe that runs from the bottom of the resonator box backwards to the boot/engine bay wall then towards the offside (UK) and then drops down towards the road with the open end about level with sub-frame.

It now does nothing on mine but it is still there - just in case I need to refit the original filter - which I have kept.

Ted
Ted Newman

Andy

I have just realised it is the height you are querying! - As I said approx level with the sump give or take a bit BUT still a lot lower than the K&N and of course it is well protected by the engine lump but still low enough in deep floods to suck up water!

Ted
Ted Newman

The standard air intake rests on top of the rear cross-bar of the subframe. I guess that's a level fractionally above the sump-bearing ladder - so I think that you are both talking about the same thing!
Rob Bell

And the standard air box has a little drain hole at the bottom but I doubt it will do much if there is a lot of water.
Spyros Papageorghiou

Put a tape measure on it this evening - 13 inches from the deck!

As Rob say it rests on the cross member.

Ted
Ted (sad git) Newman

and before any comedians jump up I am talking about the MGF Induction system and the flexi pipe.

Ted
Me again

This thread was discussed between 06/11/2002 and 08/11/2002

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