V6 wont start after cam belt change

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foxuke
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Re: V6 wont start after cam belt change

Post by foxuke » Mon May 11, 2015 9:52 pm

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Re: V6 wont start after cam belt change

Post by Cab-ova pete » Mon May 11, 2015 11:14 pm

Hi windy, you are not far from me, if you are in my neck of the woods at anytime let me know? Be good to meet up with a fellow bongonaut (notts) :D what colour/spec is your bongo? Mine is 97 green/silver 2.5 diesel 4x4
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Re: V6 wont start after cam belt change

Post by mikeWalsall » Mon May 11, 2015 11:52 pm

Never looked as I have never had reason to check .. but there should be timing marks around the front (crankshaft) pulley / engine cover that allows you to strobe the ignition timing ..

My feelings are .. if you have got the camshafts / valve timing marks set right .. BUT .. the distributor is 180 degrees out .. it will be firing on the exhaust stroke and not the compression stroke ..
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Re: V6 wont start after cam belt change

Post by Simon Jones » Tue May 12, 2015 1:01 pm

Pretty sure the adjustment wont allow it to be anywhere like 180 degrees out.
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Re: V6 wont start after cam belt change

Post by teenmal » Tue May 12, 2015 1:33 pm

I think you might find that this vehicles distributor drive is an off set dog.IE it can only engage one way.
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Re: V6 wont start after cam belt change

Post by mikeWalsall » Tue May 12, 2015 3:49 pm

I have re build various engines but never a Mazda .. I have never had an engine not start as it should (Well maybe cheat a bit sometimes .. and 'prime' the bores with a drop of neat petrol) ..

My thinking was .. Maybe the cams are set up right .. but the piston is not on it's firing stroke .. ie:- when the piston is coming up to TDC on it's firing stroke .. maybe the rotor is pointing to / trying to fire no 4 instead of number one .. ..??
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Re: V6 wont start after cam belt change

Post by jimmo62 » Tue May 12, 2015 4:08 pm

I'm not aware of the details of the V6 so may be way off the mark here but....

Piston reaches TDC on the ignition stroke and the exhaust stroke. On the ignition stroke I'd expect the valves to be close and on exhaust I'd expect at least one to be open (depending on inlet/outlet valve overlap it might be one or both).

So with the plug out and a rod down through the hole into the bore so you can see where the piston is, and with the cam covers off, you could see when the engine is at TDC on the ignition stroke (both valves closed so clearance between cam follower and valve stem) and then check the distributor cap to see if it's pointing at the right ignition lead?
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Re: V6 wont start after cam belt change

Post by foxuke » Tue May 12, 2015 7:51 pm

Thank you so much for all this. Some of it sounds familiar from my conversations with the mechanic other stuff could be new.

I am passing it all on and will hopefully get an update.
Thanks
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Re: V6 wont start after cam belt change

Post by foxuke » Wed May 13, 2015 8:34 am

Extra info -
Apparently after a night on its own in the garage when trying to start the engine coughs and sounds like it will start but doesn't. After that it just turns over.

Perhaps this tiny clue will help?
Ta
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Re: V6 wont start after cam belt change

Post by foxuke » Wed May 13, 2015 8:45 am

Windywatson - I will get the supplier for you, it was a pain finding them the first lot that turned up were wrong as the two on the driver side are different diameter to the two on the passenger side. Mark got them from somewhere in Belgium I think, will confirm.
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Re: V6 wont start after cam belt change

Post by Ian » Wed May 13, 2015 8:56 am

foxuke wrote:Windywatson - I will get the supplier for you, it was a pain finding them the first lot that turned up were wrong as the two on the driver side are different diameter to the two on the passenger side. Mark got them from somewhere in Belgium I think, will confirm.
They are part numbers 2 x JE2612601A & 2 x JE2612602A. They are available via Mazda UK, but in case of difficulty we have them in stock here at the club.
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Re: V6 wont start after cam belt change

Post by foxuke » Mon May 18, 2015 6:16 pm

OK everyone
Still no joy with my Bongo (bob).
I have copied below everything Mark has done (in blue), after all the comments above. When he refers to daves bongo that's my friends vehicle which has been used as a donor while also being serviced!

I have checked the ht leads are round the right way compared too daves bongo I have swapped crank sensor and crank pulley with daves I have swapped the whole dizzy with cap and rotor arm and ht leads, swapped the coolant sensors at the front of the engine also the ignition coil and amplifer I have even put all your parts on daves car and it runs I have checked there is no way you can get the dizzy in 180 degrees out it will not fit I have tried removing no one spark plug putting a long screwdriver down on top of the piston and slowly turning engine over till it is at tdc then checked timing marks on crank pulley lines up with marks on the cambelt cover and it does then checked were the rotor arm points and it is too no 1 cylinder on the dizzy cap. I have taken all cam belt covers off again for the fourth time and checked all timing marks on all four cam wheels line up with timing marks and crank pulley lines up with timing marks I have removed the rocker cover and checked the valves are closed on no 1 cylinder when on tdc and they are also have got hold of a cylinder leakage tester and carried out cylinder leak check which also confirms the valves are closed.

But it still does not start and only thing I can see is the compressions are low and the is a high amount of cylinder leakage past the rings.
Why this is I don't know but this is what I have found and done. So I am 110% sure the timing is right. I am going too check on daves what the compressions are and also the thing with it at tdc on crank pulley and checking no 1 cylinder at tdc and rotor arm is the same.

So Daves compessions are 100 and it starts no probs, TDC and rotor arm are exactly the same.


So what I would like now is some advice on the hydraulic lifters, there is a chance these have drained over time. What methods can be used to resolve this on an automatic engine?
Or is there something else we need to look at?

Thanks in advance
A rather frustrated yet still hopeful junior.
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Re: V6 wont start after cam belt change

Post by helen&tony » Mon May 18, 2015 7:21 pm

Hi
Just guesswork, as I don't know the engine, and I don't know how the distributor is driven on that engine, but does it have a drive-shaft that's removable from the engine? and has it been removed and put back in slightly out? The drive at the top may have a positive key-way so the dizzy is only able to be put in one way, but if it has a geared drive and it's not put in right, it will mess the whole timing. VW boxer engines are like that...you have to account for the number of revolutions the shaft takes when you re-insert it in order to get the dizzy to work well. It is possible to time it afterwards, if wrongly inserted, but it'll never work quite as it should, and you have to time it "by ear"...I had a Volvo that was probably done like that...it ran, , but you couldn't time it off a light....only by ear! It ran well but it used fuel like no tomorrow :lol:
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Re: V6 wont start after cam belt change

Post by teenmal » Mon May 18, 2015 8:12 pm

You should be able to Prime the HLAs in a bath of clean oil, as you say everything is spot on except the compressions, also This engine might need some heat to bring it back to life.

Good Luck.
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Re: V6 wont start after cam belt change

Post by Simon Jones » Mon May 18, 2015 8:27 pm

The dizzy drive is definitely keyed (probably offset) but as you say the thing that drives it may be on a worm drive so could be adrift. It should be possible based on the state of the valves and pistons in their combustion cycle to check that the rotor arm is in the correct position to send the spark to the respective plug.

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