Practically Classics Forum

Thanks for the updates Zel, will be interesting to see how that all goes.

Looks like quite a lot of oil has been flying around in that bell housing, i think i'd be trying to work out where that's come from and solve it while it's all apart....

Cheers

Luxobarge wrote: Wed Feb 19, 2025 11:19 am Thanks for the updates Zel, will be interesting to see how that all goes.

Looks like quite a lot of oil has been flying around in that bell housing, i think i'd be trying to work out where that's come from and solve it while it's all apart....

Cheers

My money is on crank seal. Simply based on the fact that the gearbox oil level was spot on when I got the car despite the plugs having clearly not been off In Some Considerable Time. The engine side is also *way* more slimy than the gearbox side.

Zelandeth wrote: Wed Feb 19, 2025 1:16 pm
My money is on crank seal.

OK, get your logic, but I'd have thought there's not a lot of oil on the crankcase side, so less likely? However, there IS a lot of pressure on the down-stroke, so I guess it could have been blowing through over time. I hope you're right, as presumably your engine replacement project will involve a new crankcase seal, so that should automatically sort the issue eh? Also if you're right you will previously have been losing a bit of crankcase pressure, so a good seal should result in a bit more power too.

I'm hoping you're going to clean up all the old oil and mess, so you'll be able to see if you were right? Half an hour with some degreaser (I use central heating oil or paraffin) and a decent sized drip tray underneath should sort that.

Cheers

Luxobarge wrote: Wed Feb 19, 2025 3:39 pm

Zelandeth wrote: Wed Feb 19, 2025 1:16 pm
My money is on crank seal.

OK, get your logic, but I'd have thought there's not a lot of oil on the crankcase side, so less likely? However, there IS a lot of pressure on the down-stroke, so I guess it could have been blowing through over time. I hope you're right, as presumably your engine replacement project will involve a new crankcase seal, so that should automatically sort the issue eh? Also if you're right you will previously have been losing a bit of crankcase pressure, so a good seal should result in a bit more power too.

I'm hoping you're going to clean up all the old oil and mess, so you'll be able to see if you were right? Half an hour with some degreaser (I use central heating oil or paraffin) and a decent sized drip tray underneath should sort that.

Cheers

The stuff on the gearbox side is actually pretty well solidified. I'll be going at it with the degreaser and a brush, but I'm not going overboard with it.

-- -- --

This afternoon I took advantage of the packaging holding the engine snugly enough to hold it at an odd angle while I attached the ignition pickup module.



Then I pulled it out of the box and used the box it came in as a workbench.



Having seen the state of the flywheel on the original engine, here's what it should look like.



Let's get this pile of boxes looking more like an engine.

Shiny new pistons.



Note that it's very important to ensure the rings are clocked correctly on these engines as there's a little pin which keeps the ring gap clear of the cylinder ports. If you don't line it up right you'll break things.

Things really went together pretty painlessly.



Somehow I managed not to even launch any of the wrist pin circlips into my face.

I really appreciate that Trabant machined a little chamfer on the bottom of the cylinder barrels so you don't need a piston ring compressor to get the barrels on.

It's almost looking like an engine now.



Yes, I did stuff a rag in that intake immediately after the photo.

Tomorrow I will hopefully get the timing set, attach the clutch, the lower engine mount and alternator bracket, then it should be ready to go in the car. Head bolts still need to be torqued down, but that will be orders of magnitude easier when it's actually in the car and held in place.

One thing I did spot was that we do have one stud that's been bent during shipping.



This is where the alternator bracket attaches. Not quite sure how they managed that as this was really well packaged. Not the end of the world, I'll just pull the stud from the old engine and swap that over. Just glad I spotted it before I was actively attaching things to it.

Couple of bits I need off here.



Yes there is actually an engine in there somewhere under all the gunk. I think most of that is actually from someone having stuffed the wrong gaskets on the exhaust ports so it's been leaking for ages.

One alternator lower bracket and one of its mounting studs.



I needed one of the studs because one of the new ones on the engine had taken a knock during transit. Thankfully it unscrewed without protesting.



Chased the threads on the old one before fitting just to make sure there was no gunk in them, though it unscrewed no bother (almost as if it had spent the last 20 years soaking in oil...) so was probably fine.

Alternator lower bracket and new engine mount attached to the new engine.



Clutch has also been installed.



I do appreciate that this engine appears to have come with a complete set of new hardware. Aside from the one stud I've transferred from the old engine because it was damaged I've not needed anything in terms of nuts, bolts etc. I thought I was going to need to reuse the bell housing and starter motor bolts, but just found new ones in a bag hiding in the bottom of one of the boxes. Definitely makes this job easier. Even though the Trabant does get points for being a car which doesn't just use twenty different sizes of fastener for the hell of it. In fact, I have a sneaking feeling having looked at them that the flywheel retaining nut is the same one that's used on the rear hubs.

I know it looks shabby, but the shipping box is actually at just the right height for me to work on the engine while sitting on the floor of the conservatory, and it deforms just enough that the engine stays wherever I put it, so it's actually working surprisingly well as a workbench.

*Hoping* that we'll get this in the car over the weekend. I want to change the two remaining engine/gearbox mounts on the car (just makes sense to do while I'm in here). I also want to clean up the bell housing a bit and swap over the clutch release bearing for the new one.

As far as the engine goes, I think once the timing is set it should be ready to go in. I just figure doing that out the car is going to be easier as access is a touch awkward in the car (especially with building supplies making access to that side of the car a bit awkward right now). Likewise the upper alternator bracket needs to be fitted, but that's one more sticky-outy-bit to get in the way while fitting, so it can be added once the engine is in place I think.

Then I just need to try to remember how all the cowling etc came apart...though it was pretty self explanatory as I recall. Should hopefully have a running car again this weekend. Well...tomorrow. Given that the forecast is for rain all day on Sunday - of course it is!

So where the heck were we? Oh yes...I had a gaping hole in the engine bay in the Trabant and an engine waiting to go into it.



First port of call was to do something about the slimy mess that was the bell housing. I didn't get carried away with this making it look like you could eat your dinner off it or anything, just got rid of the worst of the two stroke oil slime.



Actually seeing the new and old clutch release bearing next to each other does show that there was a decent amount of wear on it, though to my untrained eye it looks like there was plenty of life left in it. I think the graphite bush arrangement here is perfectly adequate as the clutch is pretty lightly sprung. One of the advantages to keeping everything small and light is it means that you can use simple solutions like this.



New one was clipped in place.



No photo of it, but I did clean up the gearbox input shaft a bit as well before things went back together.

The two mounts on the gearbox were then changed. Okay, fine I lied. The lower one was. The rear one on inspection actually looks perfectly fine (having escaped the oil contamination of everything else) and is a bit of a pain to get to behind and underneath the steering rack. I reckon it would be a doddle to do with the car on a ramp - so it's going to get done somewhere down the line when I have such an opportunity. It's not actually hindered by the engine being there or not.

This one however had gone distinctly squishy which I'm sure wasn't helping out clutch judder issues at all.



The next step made it suddenly look like I'd made a whole bunch of progress.



This was by far the easiest engine to slot in I've ever handled. It literally just slotted in - didn't even have to faff around getting the gearbox input shaft to line up. There was about five seconds of wiggling while I got the lower engine mount stud to line up with the hole in the subframe but that was it. Once the engine was actually secured in place I grabbed the torque wrench and went over the head nuts. As predicted this was far less annoying with the engine held in place.



Here's a comparison between the standard and revised alternator top bracket that's needed to accommodate the larger carburettor.



Installing the carb itself actually took about 30 seconds - though routing the new cables probably ended up occupying half an hour or so - mostly because you need to dismantle the choke cable to fit through the same grommet in the bulkhead as the original (roughly centre frame below).



All of the gubbins had to be disconnected from the cable so that it could be installed properly.



Just glad I didn't end up pinging that spring off into oblivion. It's almost like I've learned from previous mistakes in that I did that INSIDE the car with the doors closed just in case it did make a bid for freedom.

Getting there.



That little fuel filter doodad isn't actually one of those glass ones with the ends that unscrew - it's bonded together and just visually looks similar. Also made in Italy rather than China so hopefully won't be a liability.

Really wasn't that long between that stage and this stage, ready for the first start.



There was video recorded of the first start - but there may as well be no sound as it was windy and all you can hear is wind noise. On the plus side, the wind did mean that the smoke dissipated (relatively) quickly!



I was expecting somewhat biblical levels of smoke. I'd put a decent amount of oil down both bores and into the intake as I really didn't want to take any chances of the engine running dry on the first start. I was not disappointed. I'm sure our neighbours will forgive me one day.

Two bits of snagging became apparent, need to tighten the fan belt a touch, and I need to pull the cowling again most likely as the rubber pipe for the heater pre-heater connection is touching the belt inside the cowling. I'll see if I can get in there with a pair of pliers and pull it clear, but I suspect I'll end up pulling the whole blasted cowling for the fourth time. On the plus side it only takes a couple of minutes once you know where all the bolts are.

I definitely need to find the front air dam which should be below the bumper - it's primarily there to keep road spray off the rather exposed alternator and fan belt, and with that being hung down even lower now it really is very exposed.



I'm not a huge fan of this choke arrangement (well technically it's not a choke on a Mikuni though as far as the effect on the engine is concerned the purpose is the same). It's secure enough (the little L-bracket is chunky and metal) but just feels a bit shonky.



I'm inclined to just enlarge the hole in the original control's mounting point so the intended retaining collar can be used. It's a kind of odd control anyway.

The big news however is that she's moved!



Only been around the block a few times and nowhere beyond 50% throttle so far as I'm following (one of) the guides to breaking in the new engine - but should be pretty much clear to resume normal use tomorrow, though I'll definitely be exercising a bit of additional mechanical sympathy for the first couple of hundred miles.

First order of business this week though is going to be a wash!



I have cleaned the windows, but this is just begging to get pulled over by some traffic cop having a bad day with the car being this filthy (c'mon, she's scruffy enough at the best of times).

Two things have become *immediately* apparent though. First up - exactly as I expected, there were a whole selection of noises that the old engine was making that it apparently shouldn't have been. Secondly is that I really hadn't realised quite how bad the clutch was! It's astonishing what you can get used to just driving around until it's fixed.

This is what the old engine sounded like.

https://youtu.be/E4TVLcEfRMA

Now let's compare and contrast. Note that the mic on my new phone (so the new recording) tends to make things sound rattlier/tinnier than on the old one too.

https://youtu.be/CqssJvbG2EA

https://youtu.be/cXZpbviqJjc

Just a *slight* difference.

Goes without saying that I'm very much looking forward to getting back out and about in this car again now. Couple of tiny bits of snagging mentioned above to be done in the next day or two, a good clean then she will hopefully be back properly in action. I really do need to try to get some onboard video at some point - just something I kind of need a helper for I think as like the Invacar all you get is comedic amounts of shake I find with the camera actually attached to the car.

Are you having a drive put down? I spotted pallets of bricks?

rich. wrote: Mon Feb 24, 2025 9:28 pm Are you having a drive put down? I spotted pallets of bricks?

Sort of. We've got a load of landscaping work going on, including digging up and re-laying one side of the driveway which had been totally destroyed by roots from a (now gone) tree. We are also having that side extended back by a bit which is enough to gain us an additional space. Aim being that the Trabant will live there, and once the 25 moves on that will be everything off the lawn.

Sounds like a good plan.. I was impressed how easy you made it look reassembling the trabant.. are you planning to keep it? What's the plan for the 25?

rich. wrote: Tue Feb 25, 2025 1:08 pm Sounds like a good plan.. I was impressed how easy you made it look reassembling the trabant.. are you planning to keep it? What's the plan for the 25?

Much as it pains me as I love driving the thing, it needs to move on. Single biggest reason is that it's such an absolute swine of a thing to find parts for. This has been made a thousand times worse by the fact that virtually every specialist breaker in Europe I've historically used to get parts for it (and a couple of French motors beforehand) are no longer willing to ship to the UK because of the utter nonsense involved in importing goods here now. Apparently there are a couple of good groups to ask in on Facebook, but the couple of times I've tried to ask about some parts I was greeted with nothing but silence. Autodoc (and similar sites) are all but useless as their parts lookup systems simply don't seem to differentiate between the S1 and S2 cars, and the injection/carb versions...and because Renault are Renault they seemed to like randomly changing parts between versions where it made absolutely zero sense to. Autodoc don't even list the right oil filter, and if it can't even get that right, you know you're in for a bruising if you start ordering more complex items. It just makes getting hold of even the most stupid components like a set of drop links an absolute pain.

It needs and owner who has a garage, a lot of patience and ideally someone who speaks French (I did German at school!). I know some people actually quite enjoy the challenge of hunting down obscure parts, I just find it maddeningly tedious though.

It's a really good base for a rolling restoration project for the right person as it really is a decently solid car and unlike a lot of 25s is complete and unmolested, that ideal owner just isn't me though - the parts scrounging nightmare has just taken all the fun out of it for me.