Essex v6 help needed.

Author
Discussion

ferobert

Original Poster:

376 posts

190 months

Monday 25th August 2008
quotequote all
Hello, Im currently rebuilding a Hensen M30 kitcar running an essex v6.

The problem now, its not running on all cylinders on the left bank. (exhaust is only warm not hot like the other side and it clearly sounds like its misfiring and doesnt change when i pull the leads off that side.)
so far ive ported and polished the intake manifold, fitted a brand new weber 38 dgms carb with a k+n, new spark plugs, new leads, cleaned out but not replaced the dizzy, adjusted the rockers cos it was tappety, and done all the usuall service items.
I will do a compression test and see what that says, and could do with setting up timing accuratly.
Has anybody got any ideas what might be going on? Or have any info on timing these?

Also if anybody knows a good mechanic that has in depth knowlege of these engines around Edinburgh or east scotland it would be appreciated. Thanks.

rayny

1,230 posts

203 months

Monday 25th August 2008
quotequote all
Going back a few years (about 20 I think)there was a great Polish fellow in Sterling - Back O' Hill trading estate, but damned if I can remember his name,
Sorry to not be of more help, but I'm down south now

Boosted LS1

21,190 posts

262 months

Monday 25th August 2008
quotequote all
You need to check the basics first such as fuel and spark to each cylinder, correct timing, float bowl levels etc. If compression is sound could you get the car to a diagnostic machine?

hot metal

1,947 posts

195 months

Monday 25th August 2008
quotequote all
Maybe faulty carb or dizzy.Cant help with the timing but I know the timing gear can be weak on the Essex engine,made out of nylon or something like that.

ol' dirty

9,074 posts

217 months

Monday 25th August 2008
quotequote all
For it just to be miss firing on one bank (all 3 cyclinders???), I would doubt it would be the ignition timing- or it would be missing/spluttering on all 6.

Like has been suggested, check over the basics first.

Do you have the firing order in correct sequence?

Also, you could pull off the dizzy & check the inside of the cap for carbon build up & cracking- this could be the cause of your miss-fire.

Pull the plugs out & have a look, black, white or wet?

Check the points are gapped correctly (sorry, don't know the value)

Check condition of HT leads- try swapping them over with the other bank (obviously keeping the firing order correct)

When I pulled the heads off my essex, found the rear cyclinders were running lean (which I believe is common on those engines, due to the manifold design).
But have not heard of 1 complete bank not firing, its not a complex engine, so it must be very simple to cure.

If you get no joy in here, I suggest putting it in the Scimitar, TVR & Ford forums

Edited by ol' dirty on Monday 25th August 22:23

Ribol

11,399 posts

260 months

Monday 25th August 2008
quotequote all
If my memory serves me correctly isn't the DGAS the one with the geared throttles, two idle mixture screws etc?

That being the case it is effectively two carbs in one body. If one half of the carb were running very weak those three cylinders would not want to know about firing and the exhaust would not heat up.

Any good?

Athlon

5,058 posts

208 months

Monday 25th August 2008
quotequote all
Ribol said:
If my memory serves me correctly isn't the DGAS the one with the geared throttles, two idle mixture screws etc?

That being the case it is effectively two carbs in one body. If one half of the carb were running very weak those three cylinders would not want to know about firing and the exhaust would not heat up.

Any good?
Yes it is but I think the manifold makes the carb barrels feed both banks at once, i.e. the outers on one side and the centre on the other.

ol' dirty

9,074 posts

217 months

Monday 25th August 2008
quotequote all
Ribol said:
If my memory serves me correctly isn't the DGAS the one with the geared throttles, two idle mixture screws etc?

That being the case it is effectively two carbs in one body. If one half of the carb were running very weak those three cylinders would not want to know about firing and the exhaust would not heat up.

Any good?
The 38DGAS, according to the manual, does feed each bank separately via & dual inlet design. so this could be your problem then?

Each barel has separate idling & main system but is fed from a common float chamber. HTH


Edited by ol' dirty on Monday 25th August 22:53

ol' dirty

9,074 posts

217 months

Monday 25th August 2008
quotequote all
Points gapping is 0.64mm (0.025in) Got the book out now, i'll be up all night reading this nowhehe

Edited by ol' dirty on Monday 25th August 22:43

Ribol

11,399 posts

260 months

Monday 25th August 2008
quotequote all
ol' dirty said:
Points gapping is 0.64mm (0.025in)
Unless it had a Bosch dizzy like my Capri had (as opposed to a Motorcraft), in which case it was smaller, I think 0.015in rings a bell.

Ribol

11,399 posts

260 months

Monday 25th August 2008
quotequote all
ol' dirty said:
Got the book out now, i'll be up all night reading this nowhehe
Not sure which is worse, you having the book or me remembering it hehe

hal-finch

188 posts

194 months

Tuesday 26th August 2008
quotequote all
head gasket on the misfiring bank.

ol' dirty

9,074 posts

217 months

Tuesday 26th August 2008
quotequote all
Ribol said:
ol' dirty said:
Got the book out now, i'll be up all night reading this nowhehe
Not sure which is worse, you having the book or me remembering it hehe
nerdhehe

ferobert

Original Poster:

376 posts

190 months

Tuesday 26th August 2008
quotequote all
Thanks for all the input guys. Will check over all suggested items today. Im hoping it will be something stupid like me getting the leads the wrong way round. Theyre new leads so they shouldnt be the problem. Carb also brand new so should be semi set up to run out the box i guess. plugs are a bit black. Dizzy looks ok and i cleaned the arm and stud bits when building. no water in the oil so hoping its not the headgasket. Think i ought to try and find a granada haynes manual or something that covers these engines and has the technical info (firing order, gaps, timing etc) ill pop up a couple pics later cos i know we all love pics smile

Pat H

8,056 posts

258 months

Tuesday 26th August 2008
quotequote all
Blimey, I haven't seen a Henson for the thick end of 20 years.

Mk1 Granada rear lamps, IIRC?

Any pics?

drink

jagdpanther

19,633 posts

221 months

Tuesday 26th August 2008
quotequote all
If you're still having problems try either the Engines section OR the classic TVR section, they will be able to lend assistance yesthumbup

nervous

24,050 posts

232 months

Tuesday 26th August 2008
quotequote all
the v6 on my scimitar had a misfire that was eventually traced back to a failing fuel pump, have you looked at that?

Ribol

11,399 posts

260 months

Tuesday 26th August 2008
quotequote all
nervous said:
the v6 on my scimitar had a misfire that was eventually traced back to a failing fuel pump, have you looked at that?
The problem is only on one bank, that wouldn't be a pump problem.

ol' dirty

9,074 posts

217 months

Tuesday 26th August 2008
quotequote all
If you don't think it's the carb, then pull the rotor arm off the shaft & check the cam lobes for wear- i.e checking that the points open on each of the 6 lobes.

ETA, plugs could be black due to over fuelling or a weak spark, what are the other banks like?

Edited by ol' dirty on Tuesday 26th August 09:55

Ribol

11,399 posts

260 months

Tuesday 26th August 2008
quotequote all
ol' dirty said:
If you don't think it's the carb, then pull the rotor arm off the shaft & check the cam lobes for wear- i.e checking that the points open on each of the 6 lobes.
Even if there is wear on the distributor shaft isn't it highly unlikely the wear will happen to be on all three cylinders on that bank only?