Skoda 120L engine rebuild, will 130/135/136 liners fit?

[1989Skoda]

Hi, I seriously need some advice from someone with knowledge of classic RWD Skoda engines. I am trying to restore a 120L. It's pretty much rust free  but had some missing parts which I have now acquired. I bought it 5 years ago as I had fond memories of these cars from when I worked in Czechoslovakia on secondment to their forestry environmental protection ministry in 1990-91. I also owned a Rapid a little later. I have also just rejoined the Skoda owners club having been a member in the early 90s and again in 2915. My aim is to do a full concours restoration as much as possible.

 

I have stripped the engine block and discovered that two of the cylinder liners are totally unserviceable due rust caused by head gasket failure. I have been trying to source a liner/piston set from Czech and  German suppliers. Unfortunately only the larger engined sets are available, no one can get hold of a 120 set. So I am wondering if I could fit a cylinder liner/piston set from a 130/136 which are available into the 120 block? On studying photos it looks like a 130 head gasket will line up with the water passages on the cast iron 120 head. But what I don't know is if the outer diameter at the base of the 130/136 liners will drop into the 120 block and seal properly using 130 copper sealing rings? Finally the compression ratio will be raised but as the 120L is 8.5:1 in standard form then with 130/136 liners mated to the 120L head it will bring it closer to the 130's 9.7:1. I would welcome any abvice on this. If someone out there has some old 130/136 liners I would be very grateful if you could measure the outer base diameter of them and let me know.

 

many thanks for reading this, cheers Andrew

[TMB]

You could have a look at the parts catalogues here and check if any of the part numbers are matching....

 

https://skoda.7zap.com/en/cz/sk+105+20+30+35+36+garde/sko/

Edited 5 April, 2020 by TMB

[petergarforth]

The simple answer is not - the liners are larger on a 130. I don't know where you've been looking but Skopart.de list everything you'd need to rebuild a 120 - https://www.skopart.de/en/

Not sure how the lock down has affected things but he is usually very efficient and you pay and get parts in a week. Not the cheapest but the service is spot on and the stuff he has is incredible

Edited 14 April, 2020 by petergarforth

[1989Skoda]

Thanks Peter, Yes I did try skoparts but he didn't have any 120s. However I ordered a set of 120 liners and an additional spare set from Kmotorshop (ETEngineteam) from Czech Rep and they dispatched them today. I might get back to Skopart to see if he has any low compression pistons. 

 

I had toyed with the idea of boring the block out to 80mm dia with a fly cutter to take 130 liners but it would have been a very high risk operation but I did experiment mounting the block on my milling machine and it would have been possible. However I also read the that 130 conrods where wider in section so I might have encountered issues with 130 pistons on120 conrods. Anyway it would have all ruined originality. So happily I will have now liners in a week or so.

 

Do you think it is worth having hardened valve seats fitted? The current head seems not to have suffered seat recession and the valves are fine although I do have new ones to go back.

 

thanks for the advice.

[petergarforth]

I've never had an issue with valve seats on the Skoda engines - I guess if you were planning on doing a lot of miles it would be worth it or if you were going to thrash it regularly and over extended periods it might be worth it but otherwise no. It won't really add to the value and it takes 10s of thousands of miles of fairly hard driving to cause any significant damage. My race car revved to 7500 rpm and I did over a thousand miles most years for about 8 years (most of those miles were on track at 5000-7500rpm) and never had an issue. 

[1989Skoda]

ok thanks for that Peter. I think I will leave the seats alone. The car must have been run in its latter years on unleaded and they appear not to be pitted unlike my wifes modern mini which has hardened seats. I took the head off last week and had to replace all 8 exhaust valves. On another note the Cylinder liners from Kmotorshop in Czechoslovakia arrived today and look the job. They arrived in 48 hours, which is remarkable in the current situation. Next I need to find pistons although the originals look perfectly ok so maybe just new rings if I cant get hold of the pistons. Once this lock down it over I can get the crankshaft off for regrinding.  I also just rejoined the club for the third time. I was originally a member in the mid nineties when I had a 136 Rapid which I should have kept. thanks again for your advice. 

[petergarforth]

The pistons are pretty much indestructible on them so a set of rings should do - stuff isn't as available for the 120 engine because it's simply not that desirable - the 130 has bigger mains and is more durable as well as putting out a fair bit more torque and power. I take it your car has the 4 speed box? If it does you'd do well to see if you can find a 120L5 5 speed box......the 4 speed box, whilst quite durable is pretty dire and not good if you want to use the car in modern traffic conditions......fine if you're ok at 50 mph but 60-70 and things get noisy and thrashy! The 120L5 box will fit in without any modification (unless you have a mk1 or Super Estelle).

Edited 18 April, 2020 by petergarforth

[1989Skoda]

Hi Peter, Thanks for the msg. My Skoda is a 1989 Estelle two 120L and yes it is the 4 speed. If it were to be a daily driver I would agree with your recommendation regards the 5 speed box. In fact I might have held out for a 130 for the engine, transmission and rear suspension set up. Indeed in the early nineties when I was in my twenties I had a 136 Rapid as an everyday car. I also once owned a brand new 120L five and sold it unregistered with 11 miles on the clock, which I regret but I needed the garage space to restore my MGB (which I still have). Anyway with regards to my current Skoda. I bought it 5 years ago when we moved down to Devon. I somehow got interested in them again and looked for one. I was very surprised to find how rare they were. I joined the club and RPN the editor of the club mag put me onto a guy in Bedfordshire with a partially dismantled but pretty much rust free Regal Red 120L, I bought it unseen on the phone for £150 and trailered it back (600 mile round trip) behind my 1959 Landrover! It then stayed on said trailer in the back of my garage hidden behind the Landrover and two more MGBs. Finally I started to work on the engine a couple of weeks ago and I got instantly bitten again bay the rear engine Skoda bug. The engine is on the bench now totally dismantled. Its only going to be a show car so I can live with the 4 speed, in fact in rural Devon/Cornwall it might me the best option.  I cant imagine driving more than 50 miles to a show or taking it to the seaside for a day out. In any case in this part of Devon (Tavistock) apart from a stretch on the A30 our modern car never gets over 60mph! The aim is to restore it to concourse condition keeping it all factory spec apart from I may change the colour (to another year correct colour) as I  will the spraying the entire shell including underside. I fortunately acquired a lot of parts when I bought the car and put them away. It came with a new bonnet, wings front doors and three dash board, new sets of lights all of which the previous owner had stockpiled. I then bought almost every mechanical part I could new on ebay whilst they were available apart from engine parts. However I am happy now that I have the new liners. I think I have got everything else sourced now. As soon as the "lock down" finishes I will get the crankshaft off to Totnes for regrinding by 0.25mm. I will try and post some photos of the car. cheers Andrew

[petergarforth]

Oh well if you were willing to tow anything on the road in a 1959 Landrover then you'll easily be able to put up with a 4 speed Estelle......however re-sale wise a 5 speed box adds a lot of saleability and value if you weren't planning on keeping it forever. 

[1989Skoda]

If a 5 speed box came up for sale I would buy it but spares here seem to be very hard to get. My better half is Anglo-Polish so I suppose if we went on a family visit one time by car I might source one. I managed to get a band new Bosch alternator for the 120 yesterday on ebay for £42 inc post which I was pleased with. I have also ordered two sets of piston rings from Lithuania. The big end and main shells (first regrind 0.25mm) are available from Eurocarparts which I will order at some point. I am also putting together a big order from Skoda-Parts in czecho for various engine and carb gaskets, oil seals and new Czech made shocks front and back.

 

ps The Landrover is alright towing because it has a 2.5 TD200 engine transplant. 

[petergarforth]

There is a very healthy old Skoda community in the UK and quite a few people have vast stashes of spares but this isn't the place to find them. The Skoda OC has most of the people you'd need to meet and there are a number of groups on Facebook.....you will also be able to connect with the Czechs there. I've sold 2 cars in the last 2 years - both to Czechs via Facebook

[1989Skoda]

ok thanks for the tip Peter. I recently re-joined the owners club and the latest magazine arrived last week. I will explore the contacts there as you sugest.

 

cheers Andrew

[petergarforth]

David Lloyd McKinney has a ton of stuff and is super helpful

[1989Skoda]

cheers Peter