bump start

[nickk]

i.ve heard rumour that you mustn't bump the transits[06-13] with the 2.4 engine due to the timing chain tensioner being pressurised by engine oil pressure,& a possible slack chain jumping the sprockets,any evidence proving this on here.

 

[Spark plug]

I've never heard that, I know lots of mechanics that specialise in transits and they do it regularly.

 

[Johnseat]

A lot of commercial engined vehicles have am oil feed hydraulic tensioner but they are also spring loaded for when the engine isn't running so that there is very little if any slack at all.
If the steering is straight and power steering pump isn't under tension then bump starting is safe.
Be careful not to bump start if the steering is locked over as the extra strain has be known to jump the old style rubber belt cam belts.
The new style metal chain don't jump and are internal to the engine.

 

[Woody.v8]

They can and do skip teeth on duratorq engines, You are supposed to bump start them by putting them in gear with the clutch out and then start towing, I have never had one do this but I have had to repair two that have been done by others.

 

[dannyp]

transit 2.4's will jump the chain but if it dose it was going to do it anyway soon enough.

they arn't an engine that bump starts easly tho, i'm not sure if it's the right way to do it by the sounds of the its the wrong way but if we had proablms would tow it upto a denet speed and use 2nd or 3rd gear.

worth noteing if it's done about 200k and got a worn cam chain don't stall it, i've had one jump teeth and a few mates have and it's allways been on motors with rattely chain and when we've stalled them ( ether trying to pull things out, tow things we shouldn't or trying to get unstuck ) ether way they really don't like been stalled.

 

[Dee J]

Hmm what's the difference between spinning the engine with the starter or by bump starting?

 

[brightspark]

Hmm what's the difference between spinning the engine with the starter or by bump starting?

if stating engine with starter it turns slowly bump starting in a low-gear at speed pulls the -s,,hit out of it

 

[colnerov]

Hi, I've not had any dealings with them but was told, the tensioner is spring loaded until oil pressure takes over. If you turn the engine backwards or let the chain go too slack the spring unwinds with a zzzpp, so you then have to wind it up again. If you bump start them it needs a bit of finesse or a rough bump can cause the chain to jar slack momentarily when it catches and the tensioner unwinds and mayhem ensues.

Colin

Edit: beaten to it.

 

[nickk]

A lot of commercial engined vehicles have am oil feed hydraulic tensioner but they are also spring loaded for when the engine isn't running so that there is very little if any slack at all.
If the steering is straight and power steering pump isn't under tension then bump starting is safe.
Be careful not to bump start if the steering is locked over as the extra strain has be known to jump the old style rubber belt cam belts.
The new style metal chain don't jump and are internal to the engine.

well i,m pretty sure that model is chain rather than belt.

 

[normspanners]

A lot of commercial engined vehicles have am oil feed hydraulic tensioner but they are also spring loaded for when the engine isn't running so that there is very little if any slack at all.
If the steering is straight and power steering pump isn't under tension then bump starting is safe.
Be careful not to bump start if the steering is locked over as the extra strain has be known to jump the old style rubber belt cam belts.
The new style metal chain don't jump and are internal to the engine.

sorry mate but you are wrong and should not give this advise. duratorqs are well known for this problem

Dont bump start trannies or mondaos jags etc the tensioners are crap, I have first hand experience of this problem and one particular jag I was doing one would jump teeth whilst running!! putting the car on full lock at low speed
was enough for it to jump teeth.
the problem is there is not enough wrap of the chain on the exhaust inlet cam and at the other end of the cam is the water pump and power steering pump.
I fitted 3kits to it before realising the problem was that the kits cam wheels were smaller dia than the standard. I even bought a genuine Jag tensioner and it still jumped. I replaced the original cam wheels and bought the old style tensioner and it was fine. Oh and one injector that was making it miss VERY slightly so making it a little more susceptible.
Oh whilst I'm on please dont start telling me, that it is this that and the other, I checked everything many times over oil pump, oil pressure, oil pick up, had sump off and checked pick up clearance, checked cam bearings steering pressure etc etc etc. I spent days on it.

 

[Johnseat]

I've been a vehicle technician for 14 years and I've worked on plenty of the duratorq engines and this is the first I've heard of them being easy to jump teeth.
There is a known issue if the engine has done high miles with poor service history due to the chains stretching with poor oil quality being one cause, this how ever does stretch to other manufacturers as well.
There's lots of scare mongering on the web regarding bump starting ect but being a technician with lots of experience I tend to ignore it and base my posts and advise on forums on personal experience...

My first post was a general post regarding chains and belts and bump starting ect...

Also I am a systems specialist technician for a top German vehicle manufacturer which doesn't include VAG thankfully so trust me when I say that if I'd have fitted a kit and the teeth skipped then I wouldn't have decided to look deeper once I'd gone through three kits... I would have checked the components side by side for any difference and I know that's easy to write on here but that's what I do.

 

[Johnseat]

Also if this causes any offence to the OP the I'd be more than happy to remove posts ect...

 

[normspanners]

I've been a vehicle technician for 14 years

Still a kid then? try 45 ish and we are all still learning
ALL the kits had the same size teeth actually, I had to rescue the original wheels from the bottom of the scrap, I have some very good acquaintances in ford maindealers who know only to well this problem and how many times ford have tried to stop this happening and stop it re-occuring.
Just try looking on ford and jag sites and Utube etc for the problem it aint scaremongery there are lots of very good garages been stung by this problem, my friend.
In fact the week I did the one I was doing a few mths ago 4 garages locally had the same problem.

 

[normspanners]

here is one of the problems--- look at the wrap on the inlet cam on the right 8 teeth !! compaired to 17 on exhaust, the other problem is the tensioner (even with brand new chain and tensioner) allows the engine to turn back almost 1.5 teeth before turning the cams, so any back lash as you dump the clutch snatches the chain loose and before the tensioner has time to react the chain has jumped teeth.
Because the starter turns the engine slowly in comparison, allowing compression's to build slower, it doesnt cause the same violent reaction
Even ford do not advise tow starting and if it is done you are supposed to let the engine turn from a standstill in a high gear until the oil has pumped up with your foot off the clutch.
Ford have triedat least 4 different tensioners even changing the angle of the tensioner to the guides etc etc and the best tensioner in fact is one of the old style ones combined with with the modern guide.

Here in fact is the remnants of the last kit but also the new tensioner bought from jaguar with its box that only lasted 2hrs running before jumping teeth

then here is a close up of the teeth on the cam sprockets the originals where taller only by small amount but enough in my view to not allow as much movement of the chain when there was little oil pressure.

Compare the teeth to the top full engine picture above and notice the difference in the teeth

PS because of my involvement with their tech department and other people on this subject eurocarparts withdrew a certain kit, because of the problems with them.

 

[normspanners]