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Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 14:53
by CJH
I've been pondering a winter project to build a replacement engine. I currently have an early 1.9WBX, which runs very nicely. I wouldn't have considered any sort of swap if I hadn't recently noticed a little bit of coolant gathering on top of the head seal on the right hand head. There's no mixing of oil and water, no extra pressure in the cooling system, no steam from the exhaust etc etc, so I believe it is a minor issue for now, but it's a sign of trouble ahead unless I do something about it. So I'm quite happy to carry on using it for now, but I thought a good winter project would be to build up a replacement unit, so that a) I'll have a known good unit going in, b) the van won't be off the road long, and c) I can then repair the head seal on the bench, and perhaps sell that unit on as a known good runner.

I know there are all sorts of alternative engines, but I'm probably not up to doing a complete conversion myself, and anyway, I like the VW boxer sound/character etc.

So this question isn't really about what I could do to fix the current unit - from what I've read I think I already know that it could be a simple seal replacement, or I could end up with sheared head bolts, a bigger strip down for the liner seals etc etc.

The question is about whether it makes sense to build the replacement unit starting from a 2.1, or is it better to keep to a 1.9? I'd like to keep as many of my existing ancillaries as I can (fuel pump, distributor, alternator etc) as they all seem to be in good order, and if possible I'd like to run the 2.1 with my existing carb rather than an injection setup, since my carb is also in good shape and works well. This would mean I don't have to pay the earth for my project engine, since I don't really care what state the injection system is in, or the alternator, or all the computers etc etc.

The switch would require me to change to the newer cooling system I believe, since I have the 'early' pipework, but if anything, having followed CovKid's thermostat thread, this is good additional motivation for doing the swap! But I don't know for sure that it's feasible. Are all the parts readily available to do such a cooling system swap, or are there 'hen's teeth' bits that I wouldn't be able to source?

So for the experts out there, will all of my existing ancillaries work on a 2.1? Will I have to change my early exhaust to a new style - I wouldn't necessarily mind doing that, but is it easy to do?

And what sort of power boost can I expect from this capacity increase - I realise I probably won't get all of the extra power that a full 2.1 injection would have, but would I notice the difference compared to my 1.9?

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 18:50
by shepster
Without sounding rude I couldn't be ars*d reading all your post but i got the basic question, you can run a 2.1 using every bit from your 1.9 including the carb and exhaust.

If you have the early water system try to plumb the oil cooler in as well.

Many on here have gone down that route, including myself, and it is a very worthwhile upgrade in terms of power.

The main advantage is the 'grunt' you get going up hills rather than a higher top speed, there's a lot less changing down with a 2.1.

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 18:57
by CJH
shepster wrote:Without sounding rude I couldn't be ars*d reading all your post but i got the basic question, you can run a 2.1 using every bit from your 1.9 including the carb and exhaust.

If you have the early water system try to plumb the oil cooler in as well.

Haha - I wrote too much again didn't I!

What do you mean about the oil cooler - do you mean keep the old water system and fit an oil cooler, or is the oil cooler only possible if I convert the water system to the later type? Is the oil cooler a standard fit on the 2.1 - I'm asking because you said 'the oil cooler' rather than 'an oil cooler'.

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 19:01
by CJH
What's a good price for the basic 2.1 to rebuild? Does this look any good?

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 19:55
by kevtherev
That's as good as any.
The 2.1 has a little oil cooler under the oil filter
The Thermostat housing, which is plastic, has a spigot that the feed comes off to the cooler.. from the cooler it returns to the water pump.
Your mission CJ should you decide to accept it, is to provide the oil cooler with coolant from the water pump to somewhere else

Or plan for a different set up using a Mocal thermostatic type take off that sits under the filter in the same way
http://www.mocal.co.uk/index.html" onclick="window.open(this.href);return false;

Basically the 2.1 is a long stroke 1.9.
The exhaust stays the same..everything is transferable..right down to the mechanical fuel pump

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 20:41
by itchyfeet
Any engine sat for seven years will need all new head studs
As long as you are prepared for that then worth a punt at 300 but i think its still a big risk

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 18 May 2014, 22:16
by CJH
kevtherev wrote: Your mission CJ should you decide to accept it, is to provide the oil cooler with coolant from the water pump to somewhere else

OK, thanks Kev - I think I've got it. On the later cooling system that 'somehwere else' is already provided on the thermostat housing. If I want to be a masochist and stick with the early cooling system then I have to find an alternative.

itchyfeet wrote:Any engine sat for seven years will need all new head studs
As long as you are prepared for that then worth a punt at 300 but i think its still a big risk

Yep, understood. I'm kind of assuming that any WBX will snap a few head studs. If that happens to an engine that's still in the vehicle then it's a big problem, but an engine that's being dismantled in my garage could be taken to someone with the right facilities (welding a nut on seems like the favoured approach). What about reassembly - running the right coolant is the best way to avoid the corrosion that causes these snapped studs, but is it possible to get stainless studs? Any stainless fixings I've used seem a little softer than ordinary steel - would that preclude stainless for head studs?

I'm not in a hurry to find an engine to start on - it's a potential winter project after all. What should I look for in the donor - is it expensive to replace the liners and pistons? Cracked heads need to be avoided obviously (although I don't know how you can tell before you start disassembling), but what about the crankshaft and case - is there any way to be sure I've got a good starting point if the engine is already out of the vehicle?

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 20 May 2014, 17:55
by mark
if its out of the van, look for coolant deposits around the heads, give the pulley a good yuck to check for end float, check the condition of the oil for coolant, how black and thin it is will tell how well its been serviced, have a sniff for fuel, check the plugs, deposits will/could tell how well it was running before it was removed, oil leaks along joints and where things pass into the casing, exhaust studs. I cant think of owt else.

mark

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 20 May 2014, 18:49
by CJH
That's brilliant - thanks Mark.

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 08:24
by croc
CJ
I would be sceptical of stainless for head studs.
Stainless is prone to fatigue if vibrated ... and it would seem that with those studs being vibrated every time a piston fires would be a good source of vibration ... no?
I know its not recommended for the engine mounting bolts in inboard engined boats. The fatigue caused by the vibration causes them to snap without warning.

Also, with proper coolant the standard studs aren't a problem - there's thousands of them out there...

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 09:06
by kevtherev
Vw changed the stud metalergy mixture after 86. to a less corrosive one

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 09:54
by CJH
Thanks guys. OK, so assuming I'm going to replace at least some of the studs in any engine I rebuild (and why not all of them), are studs made from this improved mixture readily available?

In fact, why don't I broaden that question. Are there any parts that simply aren't available either new or in good supply on the second hand market? I'm thinking, pistons, liners, con rods, bearing shells, valves, springs, guides etc. The last (only) time I rebuilt an engine my current van was just rolling off the production line, and since that engine was from a 10-year old Triumph everything was easy to get hold of.

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 11:52
by kevtherev
Look.
Getting head nuts off is just easy, all you need is a lot of red heat.. (and the studs are available.)
the only thing not available is the crankshaft and maybe the camshaft
For the repairables, Heads come with the valves, the lifters, pistons rings and barrels, bearing shells, various seals are all OK to get.

never assume. :D it makes an ass of u and me

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 12:10
by p373r42
Had to laugh when I read this post as I had the same idea, and have even been looking at the same engine on Ebay.
Anyway funds have dried up for now so its not going to happen.
Without any history of the engine I would strip it completely and check the bottom end as well. How would it feel to recondition the top end only to start it up and have little or no oil pressure.
As Kevtherev says dont assume anything.

Re: Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

Posted: 21 May 2014, 12:19
by CJH
If I'm reading him right, I think Kev is saying not to assume that the studs will need replacing, so I'm erring on the pessimistic side I guess. But if the head nuts come off reliably with heat, then maybe they won't break, and maybe they won't be corroded.....

But I'm with you - I'm certainly planning a complete rebuild. It's not because I desperately need a new engine or more power. I've got a garage I can heat in the winter, and it's something I can do after the clocks go back and I can no longer work outside on the van. It should be a useful learning experience at the very least.