Not firing on all cylinders

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muddy
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Not firing on all cylinders

Post by muddy » 16th November 2017 - 9:10am

Ok so now that I’ve sorted the oil cooler leak I fired it up last night after moving distributor to get it started.

After a short while I noticed that the passenger side exhaust was hot and the drivers side was cold.

The car sounded ok, the engine does need the timing sorted.

It’s an injection engine. One point to note is I had my injectors rebuilt and I think you can put the plug in either orientation. Would the plug in the wrong way in the injector make a difference?

It’s one problem after the other at moment, my brand new CSP rear brake calipers are weeping brake fluid via the bleed screws.😩😩
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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broady_6
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Re: Not firing on all cylinders

Post by broady_6 » 16th November 2017 - 8:38pm

have you checked the basics? First thing is the valve to rocker clearances, then check theres a spark at each cylinder and at the right time. Then check for compression and fuel.
The sultan of swing

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 16th November 2017 - 8:43pm

The joys of building an older car :)

First I suggest you need to establish whether the it is a fuel issue or an ignition issue. Use a spare plug, connect it to each of the right hand side plug leads in turn, earth it to the fan housing/ crankcase as appropriate and with the help of an assistant to crank the engine over make sure both cylinders are getting a spark.

If not, it's an ignition problem, if they are sparking, then make sure the plug leads are on the dizzy in the right orientation. Remember firing order is 1-4-3-2, so the plug leads need to be connected in that order - check the direction of rotation for the dizzy first ;)

If the ignition side is OK, then the problem must be fuel. The trigger points within the dizzy are a common cause of problems, so clean them but do NOT use anything that will abrade them away, in other words brake cleaner / contact spray and cloth only. (Editor is very forceful on this point) :)

Take it step by step and we'll help you get there :thumbsup:
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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muddy
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Re: Not firing on all cylinders

Post by muddy » 16th November 2017 - 10:12pm

Thanks guys, your don't realise who much your helping, the last few weeks have been a struggle and very testing.
I'm not going to touch the engine now until Sunday as a mechanic friend is going to help me try and figure out what's wrong, I'll be sure to look over everything you guys have suggested.

I've been working on a horn fault all night, ended up being both the copper spring on the indicator stalk and the brass rings on the steering wheel. Could have sworn the horn worked when I bought it. Oh and the actual horn is knackered too.

I'll keep you updated.
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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Editor
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Re: Not firing on all cylinders

Post by Editor » 17th November 2017 - 1:17am

I rarely get a working horn when checking before it goes for MoT. There's been a lot of discussion about '73 horns where the spring contacts on the indicator switch assembly wear through and snag things internally. Unfortunately the 4-spoke steering wheels need a bit of care pulling off the pad as the plastic lugs tend to fail if they're removed too often. I guess VW would have simply replaced them.

I suspect the horn can be mended, but it's not easy to get the right thickness of gasket to allow proper operation once reassembled.
Dave.

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 17th November 2017 - 8:16am

Some bedtime reading for you before your mechanic friend comes on Sunday :)

http://p914-6info.net/PDFs/D-Jetronic.pdf

Don't worry about the manual being for the Porsche 914, it's the same basic system.

You might want to edit your profile to show your location, it's not unknown for people to help in person
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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muddy
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Re: Not firing on all cylinders

Post by muddy » 20th November 2017 - 9:36pm

Right guys here's an update. Made some progress.

So yesterday we checked the ht leads were in correct places and that they all had a spark.

Removed ht leads on cylinders 1 and 2 and there was no change on cylinder 2.

Ht lead ok, spark plug ok, which leaves fuel and the injector.

Checked injector plugs for voltage and both ok.

Removed both injectors and swapped them over. The non working cylinder moved position indicating that the fault was the injector.

I've spoken with the guy who rebuilt the injectors and he suspects that it may be stuck as it had been several weeks just sat in the engine without fuel. He suggested to fit injector and whilst engine running give it a hard tap to try and free it up.

So tonight I've refitted the injectors and started it up. Even before I've tapped the bloody thing it works, as exhaust was getting warm and when I pull the ht lead the engine noise changes.

So that's one saga sorted, so engine is running and sounds ok.

Next saga is that yesterday we fitted the doors and they don't align up with anything. 😡

So it looks like the next week I'll be on this. I might get this on the road sometime this millennia.
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 20th November 2017 - 10:10pm

Well done :thumbsup: another issue resolved.

You might want to consider treating the fuel system with a cleaner. Forte is my go to - based on independent advice from two specialist garages. Alternatively fire the car up regularly and enjoy the sound :)
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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muddy
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Re: Not firing on all cylinders

Post by muddy » 21st November 2017 - 12:08pm

Funnily enough I was going to ask the forum what recommendations are there for additives and to combat the ethanol and old fuel issue
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 21st November 2017 - 2:24pm

There's ethanol in all pump fuels, Tesco Momentum achieving its higher octane from ethanol addition. You should make sure that your fuel lines are suitable for todays fuels. It's a bit of a lottery, you can buy fuel hose with all sorts of claims and it'll rot quickly because it isn't what it says on the tin. I bought some Febi (Bilstein) branded for my 412. It makes no claims for biofuel compatibility and I haven't had any deterioration. ........... unlike the rubber elbows for the carb balancing pipe where I bought VW product and it perished within 2 years.

Old fuel, there is only one solution really. Drain it off and find another use for it. The fuel will be off, so not good for driving (but probably OK for garage use, unless it's really rusty). That's where the problem lies, I've got away with it many times but I was re-commissioning a car earlier this year, put a new fuel pump on it and within minutes the crud that came out of the tank caused it to seize, so I had to buy another one :(

Do a search as well, there's lots of opinions on the fuel hose / ethanol issue (now going back to replacing the vent / breather lines on a T25 fuel tank)
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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broady_6
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Re: Not firing on all cylinders

Post by broady_6 » 21st November 2017 - 6:31pm

Well thats good news and a simply fix!

I also didnt realize forte did fuel additive, I carry a bottle of there cooling system repair in my race kit its bloody good stuff. I will investigate the injector cleaner.

I can also recommend the millers injector cleaner, ive had a good results at least 3 times now.

http://www.halfords.com/motoring/engine ... omax-500ml
The sultan of swing

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muddy
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Re: Not firing on all cylinders

Post by muddy » 21st November 2017 - 8:23pm

Thanks for the recommendation's on the additives, I'll definitely use the injector cleaner. The injector bloke who rebuilt my injectors recommended Stabil to maintain fuel longevity and quality and stabil to protect against water in fuel.

I'm guessing I couldn't use multiple additives at the same time? I also wanted to add an octane booster like Millers VSPE for classic cars.



Been back on the car tonight, finishing off the long list of finishing off jobs to do. I'm trying to get the front wheels straight but having a mare as I keep running out of rod length and tie rod length. Also the tie rods have caught my gravity brake line and pulled one of them from the master cylinder letting brake fluid out. I hope I can get away from not having to bleed the whole system again at least for the immediate future. Pedal still feels firm.
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 21st November 2017 - 8:53pm

Stabil sounds like an equivalent of what the Yanks use for fuel stability and elimination of varnish revenues in small engines "Sea Foam" is the brand.

Be careful with octane boosters. You might think that a 1 point improvement would move the octane from say 95 to 96 RON. It doesn't, I used to use one (pottasium based) for a specific purpose, knowing that 1 point improvement was actually only 0.1 RON change.

I just fill up with V-Power, 98 octane and with decent a decent cocktail of additives out of the pump. It's what I use in pretty much all my cars (classic / daily driver / race). The differential is about 12p / litre, so a 50 litre fill up costs £6 more. Probably about the same as a bottle of additive.

How are you doing the tracking. Do you have a set of gauges or a trusty piece of string and a rule ? I'm not sure how different front / rear track are on a type 3, but as a starting point, and if the back end is somewhere near, run a piece of string or a straight edge from the rear wheels to the front one one side, make one side parallel and then deal with the other. It's a bit obvious, but you also need to ensure that when the wheels are in the straight ahead position, the rack/recirculating ball is also in the middle of its range of movement. You can then put the steering wheel on the correct spline for straight ahead and tweak for final centering / alignment.
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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broady_6
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Re: Not firing on all cylinders

Post by broady_6 » 21st November 2017 - 9:42pm

A little tip ive learned from the industry is to stop fuel from going off, add a little av gas. a liter per tank will help no end. Most club air fields with have a pay at the pump style outlet so you can buy yourself a jerry can full and add it when needed. its also 100 octane!

Not knowing where you are I cant help by saying I can buy some for you from work.
The sultan of swing

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muddy
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Re: Not firing on all cylinders

Post by muddy » 23rd November 2017 - 8:31am

Thanks 937carrera and broady.

Regarding the tracking, I just want to get it in a ball park region so it's driveable, and get it done by my local garage who do our dailys, they have a hunter setup. I'm finding it more difficult to set a line when the fronts are tucked in due to the narrowed beam. I'll get it sorted though, just takes a bit of time and patience.


I plan on stepping away from the car for a few days, as it's doing my head in. I've noticed that the rear suspension height is 30mm different?? So don't know if this is the new shocks or that I need to redo one side 1 spline. I'll remove both shocks and see how it sits naturally to tell if it's one or tuther. Will be gutted if I have to strip it all down now after being all painted.

Still have to do the door set-up and alignment too.
1971 VW Type 3 1600 TE Fastback. Body off Resto completed, now just bits and pieces and niff naff to do.
Volksworld Magazine featured car 2013
Instagram: @type3.fastback

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937carrera
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Re: Not firing on all cylinders

Post by 937carrera » 23rd November 2017 - 9:51am

Narrowed beam means the piece of string method won't work. Alternate method is a long straight edge forward from the wheels and chalk marks 4-6 feet from the wheels. Measure the track "outside to outside", then get a calculator if you are setting by angle and use trig, or set in mm and ratio for the additional distance. If you only need it driveable, just set it up to parallel by eye

Unless they are self levelling or jammed, dampers don't change ride height..... but I think you already know that ;). I don't know how much difference one spline makes on a type 3, but I'm sure someone will, if it isn't already posted.
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon

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