Fuel injection rebuild

[Simmy]

Hi everyone!

So this would be my first post on the site, but I have been stalking the forums for a little while now. The reason for my joining is that I have been trying to build momentum with this project, but I seemingly always find something to stumble on before it goes quiet for months on end. I am hoping that with the knowledge that is out there on the forum and the idea that I should keep documenting the build will keep me on track this time. So I guess, a thanks in advance is required

Some history on the car:
This is a 1978 model, which was my uncle's first car, so it has been in the family since then. It was given to me back around 2000, when I started the restore with the help of my dad at the time. We got the car running by about 2005/6, where we had the entire body resprayed and the interior refurbished. Almost all the electrics were painstakingly redone. We tried to get all of the basic functionality of the car right, so all of the heaters, vents, latches fittings etc. all fit the way the Germans always intended.

We left the engine and gearbox stock, but fitted the stainless extractor exhaust and polished the inlet manifolds, but that was about the sum total of the performance mods. Then I got enthusiastic and decided to fit a fuel injection system to the car, which was sold to us by Volkspares. I am hoping there are some here that are familiar with the "kit" because it was sold without instruction and quite a few parts that didn't even fit together, so I have largely had to figure it out as I have gone along. I will admit that I have a fair idea as to the theoretical aspects of the build but I am often left stuck on some of the technical aspects.

Unfortunately whilst I was busy with the fuel system, my dad, who had been a major feature of the build and my primary source of knowledge on all things Beetle, passed away (hence I found another reason to put the work on hold). As a result, it is about time I got this thing moving as I really miss the old car and its character.

So, just as a summary, here are things I think I still need to achieve before being able to at least start the thing:
- run the wiring harness through for the fuel system
- figure out how to wire some of the bits
- install all of the flexible fuel hosing (thankfully I am done with the hard lines). I have always wanted to fit stainlesslines AN fittings, so I will have to save up a bit for those.
- fit a larger bore brake master cylinder (we fitted the disks all round, but no one told us that the standard cylinder didnt generate enough pressure to adequately use the brakes... just learned to do a double pump on the brakes as a temporary solution)
- Modify the hand brake lever to accomdate the larger movement required to activate the calipers
- trial fit all of the tinware to see what I have missed
- Drain the oil since it has been sitting for years
- Replace the swing axle boots since they have perished
- Replace or lengthen the throttle cable as it looks like it will be too short
- Replace a number of other rubber seals which have perished over time

And that is blurb over...

So here are some pic's that I tool yesterday to illustrate some of the progress.
I would liked it to have been cleaner, but I have had it on stands for a while, so I couldn't easily get it out for a wash.

The car:


The fuel pump & lines fitted (still need to deal with the brakes)


The fuel pump - a little more on this later


The interior


The engine mocked up to just refresh myself (again) as to where to go next.

[Simmy]

So one of the biggest issues I have faced are the electrics - I really dont understand them and the wiring is just everywhere. When I have tried to figure it out, I get frustrated and irritated with the thing. I think I have got the jist of the fuel system wiring and will likely need assitance later when I need to start the car (but I will worry about that later), but I need some input on the following:

The fuel pump never came with a weather proof fitting. I have tried to google the pump, but have never had much success in finding out what type of connector it uses. Volkspares suggested that I just use a standard spade connector on the terminals, but I always hated that idea as it is liable to shorting given that the plug forms its own tiny reservoir:



Secondly the distributor also has a missing fitting - It looks like the TE connector featured here (http://za.rs-online.com/web/p/automotiv ... s/7186867/) which are the ones supplied for the injectors, but this looks like it needs longer terminals to reach the contacts. I think this is the right one, but i have no idea where to source such a thing (http://www.ebay.com/itm/3-Pin-Female-Co ... 1902728910)



The ECU is a Gotech-MFI unit and comes with instructions for numerous setups. To be honest, I really dont know which option to select at times, so I wanted to ask for some insight:

This first page describes the distributor connection. I think it should be the one one circled. I think it is a fairly standard distributor, but I really dont know anything about it other than it is supplied as a Tonii distributor, for which there is little to no info online.



Next is the injector layout. From the options below, I think the Mode 0 is most applicable since I dont have VVT or a TDC sensor (but could be wrong here). Unfortunately then I am presented with the options for wiring injectors vs microfuellers. From my understanding, I should be using the injector layout as a microfueller something completely different.







Then lastly, it asks for an oil temp sensor to be fitted. From what I have read, I believe the best place to fit one is one in the Oil Pressure Relief Valve, so my plan was to do so there. What I wanted to know was the type of thread used here so that I can source an adaptor for the sensor that came with the kit.

[Tony Z]

Not sure how much this post will help you, but I'll give it a bit of a try.
The first thing I would do is remove the copper hard lines and replace them with stainless. The reason is that copper work hardens which will eventually lead to cracking. This work hardening is caused by vibration - and a car vibrates a lot. Some people say I over cautious with this and it doesnt happen in a car - I prefer to avoid the issue altogether.

@4agedub might be able to help with your Gotech issues. Otherwise, contact Gotech directly and visit them with printouts of your setup.

As for the oil temp sensor. There are two reasons for this.
1) to run an external oil cooler and fan, the fan turns on at a specified temp via the gotech unit.
2) it tells the Gotech unit when the engine is warm so that it can switch from the rich cold fuel maps to the leaner warm maps (basically a modern version of the manual choke.
If you are not using the fan start switch (or if the Gotech unit doesnt have this feature) and you are only monitoring the oil temp for the fuel maps, then you can mount the temp sensor anywhere that it can pickup when the engine is warm. It doesnt need to be accurate - just set it so when the engine is warm enough, (even 50deg) then it switches maps. You could monitor the oil temp by putting it onto the side of the sump or onto the head near to where the rocker cover fits on. If it needs to be accurate, then it needs to be either in the oil flow (getting fresh oil flowing past/over it) or it could be in the sump or sump plate.

Hopefully this helps.

[Simmy]

Hi Toni. Thanks for taking the time to respond.

Your point regarding the fuel line is noted. The feed line is a different material - thought it was aluminium given its ductility. Again one of those things that came with the kit and didn't think to question. I fitted the copper line because I happened to have it and it was a damn sight better than using the standard line for the return (as I was initially told to do).
I will certainly look into refitting something different.

Thanks for the clarity on the temp sensor. I did see that a tapping into the cylinder head was recommended by CB performance, but the MFI unit specifically requests water or oil temp, for the reasons you already stated. Also, the prospect of pulling the engine out to tap this one hole did not seem appealing. Note, i see now that it should be an M18 thread (as per the VDO temp sender for this duty) so I will see if I can get something to fit once I drain the oil.

[Tony Z]

VDO makes sensors with much smaller threads. I am sure you can source one of those and use it if it makes it easier.
Check what output yours gives when it warms up and get another which does the same or similar. The one I use for my gauge is approx M8 but is a fine thread. Check their website, they have plenty options available.

[Simmy]

Although its been a little while since the last post, there has nevertheless still been a bit of work on the car. Primarily around the electrics along with some more research to try and ensure i dont screw anything up with the build.

I landed up draining the oil so that I could get to the relief valve for the temp sensor - no real problems there. It turns out it is an M18 thread, whilst the sensor is an M10 fine. I am going to see if I can get a different sensor this week from an auto-electrical supplier along with a few other bits (If anyone can recommend a place preferably in the Randburg area, I am all ears). If not, then I will have an adaptor machined.



You will note that there are quite a few oil leaks Although the car has been sitting a while and there is oil everywhere, I think the majority of it is coming from the output shaft seal (purely based on the fact that it originates ahead of the sump plug). I am in two minds as to how to deal with this... since the engine has mostly been stripped already is much easier to pull it out and deal with the leak now... or I just clean it all up for now so that when it is running I will be better able to confirm that I am diagnosing it right.











I am also fairly sure that there was a leak coming from the filler / alternator pedestal which I will resolve later as well as from the cooler. One minor leak was noted at the case seal for cyl#2. I don't think this would be considered a major problem, especially for an old stock engine such as this.

There are also two leaks on the gearbox - one at the selector input, though minor, and one at the drain plug. I would like to think that tightening the latter up a little more would resolve this, or would it be better to use a little teflon tape to help seal the thread?

[Simmy]

Just a couple of other things I managed to resolve:

1) Regarding the wiring of the distributor:
Firstly, I confirmed this is a hall-effect type distributor by taking it apart and poking around the internet. Thankfully this means my initial suspicious were correct. I also found this seems to come from a golf Mk2, so I managed to source the plug from VW in Randburg and should get it next week.

2) Regarding the fuel pump and lines:
Did a little more research into the copper fuel line problem, and I think I will be replacing that line. I also just wanted a second opinion on the fittings I made up to secure the line:



They are supported every ~20cm, which I felt was sufficient to avoid vibration and wear, but I have seen suggestions that I should rather use rubberised P-type holders / fittings. I would like to think that what i have done is acceptable, but I might just run a bead of silicone behind the line to make absolutely sure that vibrations are damped.

Also, the pump seems to come from a Mk2 golf as well, so I managed to source a plug for that as well from VW. It was a tricky bugger to find...

[Simmy]

One last question for today:
Anyone know what the purpose of the silicone tube on the ECU would be for? I assume that it is to read manifold pressure for the purpose of detecting engine load, but I cant find anywhere to confirm as much. I cant imagine that it would be necessary to measure atmospheric pressure using this... it just seems a little redundant if that is the case.

[Wentzel]

Hi, yes the tube is for manifold pressure/engine load. If I remember correctly you can use it alone or with the tps sensor when tuning to determine load and throttle position.

[Tony Z]

For the drain plug leak, you should be able to stop this by either annealing the copper washer (if its a copper washer and not the VW style with O-ring inside the washer) or replacing it with new, or with a copper washer or a bonded washer.
For the crank shaft seal leak - attend to this while its easy to pull the engine. If you dont do it now, you'll dread having to go through the effort and you'll avoid it for as long as possible.
With your fuel line - I wouldnt do it like that, but thats me. Keep an eye on it to make sure it doesnt chaff. Or wrap it in a rubber hose where you clamp it down. 2cm long and cut open.
Before you edited your post, you asked about the oil pressure relief spring. Thats a calibrated spring (to a point) and needs to remain unaltered in position.

If you are really desperate for a location for the oil temp sensor, you could consider a custom oil drain plate with the temp sensor in the place of the drain plug, or a second hole for the temp sensor.

I have got new gearbox input selector shaft seals (I think I have 2). R250ea.
I've also got Elring crank shaft seals R145ea - these are the best you can get.

[Simmy]

Thanks for the input guys.
I updated the post since I found some if the answers​ I was looking for whilst reading. I should probably update it with the answer instead of clearing the question in future.

My plan for the coming weekend will be to pull the engine out. As Tony pointed out, it doesn't make sense not to at this point. Whilst it is out, I think I also need to consider taking of the heads to fit new valve seats... I believe that the standard ones need to be replaced in order to run on unleaded fuel.I am not even sure that one gets LRP any more?

I'm now fairly happy with the temp sensor and it's location. Since the sensor is calibrated for the ecu and a new one costs about as much as a machined adaptor, I will just go that route.

I will also deal with the fuel line fitment. It seemed like a good idea at the time, but having no frame of reference, I will err on the side of caution.

Good news though, the wiring under the rear seat is basically done...

[Tony Z]

unless some butcher modified your heads, then they are already good to go on unleaded.

[Simmy]

Certainly no butchers here... everything still stock.

Clearly I need to do more reading... I was always under the impression that there was a risk of deterioration without the lubrication from the lead.
(Now I have one less reason to tell my wife that I need to buy / modify a new set of heads )

[Tony Z]

on the very very early beetles yes, but otherwise its not a problem.

[Simmy]

So I got the engine out after a little bit of heave-ho... Aside from having to remove the exhaust it was relatively pain free. What i failed to recall was that the aftermarket exhaust catches on the bodywork, so you cannot get it off the gearbox input spline without doing so.


What I have managed to establish is the following:

• There is definitely a leak from the output shaft as I suspected. Looks like I am going to need to take you up on that seal offer Tony

• Much of the rest of the oil is coming from the sump as well as the oil filter / pump. Unfortunately with the all the mess there, it is difficult to confirm exactly were it is coming from, but I hope the there isnt a leak coming from the plug seen in the same image (I presume it is one of the plugs sealing off an oil gallery.

• The pushrod tubes and tappet covers are leaking pretty badly on the side of cylinders 1/2.

• There looks like there is also a relatively significant leak coming from around the barrel seals on the same side.

• The opposite side is cleaner, but not void of crusty oil gunk

• Lastly... my favourite, oil in the intake ports. On both sides. I assume this is a function of worn valve guides?

At this point I need to ask for some advice... not sure if this forum or the advice section is the right place to do this, so I will just start here and move it to a new thread if that is regarded as correct forum etiquette...

• I certainly have to take off the heads to get the pushrod tubes fixed. I happen to have a set of adjustable aluminium ones - albeit from EMPI -
  but I have them nonetheless.

• I am wondering if it is worth considering opening up the case and getting it refurbished... Not sure where that rabbit hole leads...

• If I am starting to open up the case, then I am thinking it is worth while making the most of the occasion and fitting a new c/w crank and cam and some other fun bits. I am well aware that none of this is an inexpensive exercise, but I would like to think that these cars struggle to lose value, so whatever I do could be considered an "investment"

• Lastly, I would like to be able to do the assembly myself (never built an engine before... which I am really keen to try), but I would certainly need the help from a seasoned veteran when it comes to the fitting and turning

For now, I have some more reading to do to try and formulate my next plan of action. Thus far I am leaning toward something along the lines of a Mild street engine spec given by Keith Seume in his book "Aircooled VW Engine Interchange Manual", but with this feeling that I would like to turbocharge it in the long run (I have always liked the idea of a small turbo especially given the reduced plumbing complexity with the single throttle body).
Anyway, I would really appreciate your thoughts and opinions on the state of the engine at present. Feel free to chip in with your thoughts of an upgrade too.