One of my regular readers was unable to upload to the "comments" and as a result asked me to post the following email exchanges; the information should be of interest to all I think.
1.
Hi Paul,
I read your bottom end article with great interest and reading it I have three questions:
1 why have you used the cylinder base gasket if rigidity is such an issue? If you machine chambers for o-rings around the oil passages to the head and use a good silicon base sealant for the rest the stiff cast iron block directly bolted to the 'flimsey' crankcase will surely stiffen things up.
2 The 1600 engine you are working on has main bearing studs instead of bolts complicating the assembly but what is the reason to use them?
3 have you ever experienced with a mainbearing cap brace to stiffen up the running path of the crank?
Cheers,
william
PS I tried to upload these question via the blogger page but did not succeed.
2.
Hello William,
I suppose that I am speaking in rather "absolute" terms regarding the rigidity of the crankcase and this is not my car! We used to do what you described - 'O' rings etc. when I was in London - there we had the necessary facilities.
The crankcase was, as you know, originally designed for a 58HP 1100 saloon car so stretching the engine to 1600cc when the company was going broke was bound to lead to some compromises! The studs are lovely things, waisted for stress relief like the big-end bolts and the thread size is 12mm rather than 10 as on the 1300s; this is why my friend used a 1600 crankcase for his 1486 project. I have no iew really on the choice between bolts and studs, but the studs are not really more complex are they? I think I prefer studs to bolts though because I suspect that unless special dowel bolts are used, location is probably more accurate.
The idea of a main-bearing support was one we used to discuss a great deal and I believe that VERE Lancia offers one. An excellent idea I think. Even better would be in addition to cross bolt the caps as was frequently done in aero-engines and other high class motors. This would be difficult given the thinness and weird shape of the Fulvia's crankcase!
I have been busy on the Fanalone but have terrible Internet problems and so have been lazy on my blog. The subframe is now assembled and ready to go in; I'll write it up when I have a chance.
best wishes
Paul
3.
Hi Paul,
Thanks for your replies. You might want to upload them to your Blog article.
In my 1200HF engine I have fittted M10 APR studs. Albeit not waisted like on 'your' 1600 engine. The torque value as now 8Kgm compaired to the 5Kgm of the OEM 10.9 bolts.
I have also used the omicron supplied APR conrod bolts. Expensive but since nobody knows how many times their OEM bolts were (over) torqued in their 40 year lifespan a good insurance.
I have seen the brace Vere Lancia sells and I'm not very impressed by it. Too many curves and thin spots. Can't be very stiff and it is expensive at around 400 euros. I have made one from sheet metal angle iron. See picture. Stiffer and for 5 euros it is extremely cheap!
Cheers,
william
1.
Hi Paul,
I read your bottom end article with great interest and reading it I have three questions:
1 why have you used the cylinder base gasket if rigidity is such an issue? If you machine chambers for o-rings around the oil passages to the head and use a good silicon base sealant for the rest the stiff cast iron block directly bolted to the 'flimsey' crankcase will surely stiffen things up.
2 The 1600 engine you are working on has main bearing studs instead of bolts complicating the assembly but what is the reason to use them?
3 have you ever experienced with a mainbearing cap brace to stiffen up the running path of the crank?
Cheers,
william
PS I tried to upload these question via the blogger page but did not succeed.
2.
Hello William,
I suppose that I am speaking in rather "absolute" terms regarding the rigidity of the crankcase and this is not my car! We used to do what you described - 'O' rings etc. when I was in London - there we had the necessary facilities.
The crankcase was, as you know, originally designed for a 58HP 1100 saloon car so stretching the engine to 1600cc when the company was going broke was bound to lead to some compromises! The studs are lovely things, waisted for stress relief like the big-end bolts and the thread size is 12mm rather than 10 as on the 1300s; this is why my friend used a 1600 crankcase for his 1486 project. I have no iew really on the choice between bolts and studs, but the studs are not really more complex are they? I think I prefer studs to bolts though because I suspect that unless special dowel bolts are used, location is probably more accurate.
The idea of a main-bearing support was one we used to discuss a great deal and I believe that VERE Lancia offers one. An excellent idea I think. Even better would be in addition to cross bolt the caps as was frequently done in aero-engines and other high class motors. This would be difficult given the thinness and weird shape of the Fulvia's crankcase!
I have been busy on the Fanalone but have terrible Internet problems and so have been lazy on my blog. The subframe is now assembled and ready to go in; I'll write it up when I have a chance.
best wishes
Paul
3.
Hi Paul,
Thanks for your replies. You might want to upload them to your Blog article.
In my 1200HF engine I have fittted M10 APR studs. Albeit not waisted like on 'your' 1600 engine. The torque value as now 8Kgm compaired to the 5Kgm of the OEM 10.9 bolts.
I have also used the omicron supplied APR conrod bolts. Expensive but since nobody knows how many times their OEM bolts were (over) torqued in their 40 year lifespan a good insurance.
I have seen the brace Vere Lancia sells and I'm not very impressed by it. Too many curves and thin spots. Can't be very stiff and it is expensive at around 400 euros. I have made one from sheet metal angle iron. See picture. Stiffer and for 5 euros it is extremely cheap!
Cheers,
william
4.Hello.
Congratulations on what looks to be an interesting solution - the only thing about steel of course is its different coefficient of expansion from aluminium, though I suppose if there's not too much mass you shouldn't have much of a problem.
Have you run the engine since you installed the brace - and if so have you noticed any difference?
I like the idea of the studs and the special nuts look very aerospace which I am sure they are! As for con-rod bolts I used to buy 1300HF ones from Cavalitto - they weren't too expensive and at least for the 1600 Lancia said that the bolts must not be re-used, so I think you've been very wise - mind you I've got away with it for 28 years!
I'll try to post the exchanges on the blog if this rotten Internet connection ever works!
Regards
Paul
5.
I have run the engine for about 2000Kms with the brace but cannot say that there is a difference since many other parts were also modified and as I wrote in earlier mails the main bearings were found worn due dirt in the oil. That is all repaired now by grinding the crank to its first undersize and I'm now running the engine in again. But the gear box started to develop a massive oil leak last week coming from the prise shaft and this is another setback as the whole subframe assembly has to come down again in order to be able to remove the gearbox....
Keep you posted!
William
6.
Hello.
So it was dirt in the oil? I am surprised!
As for the gearbox, that of course is a common fault. The roller bearing and seal(s) are always a weak point - especially in the very early 'boxes which had only one seal.
The way I tackle the problem is to remove the engine, drain the 'box and remove the bell-housing; that way you don't have to drop the subframe - or worse, the gearbox!
Regards
Paul
Congratulations on what looks to be an interesting solution - the only thing about steel of course is its different coefficient of expansion from aluminium, though I suppose if there's not too much mass you shouldn't have much of a problem.
Have you run the engine since you installed the brace - and if so have you noticed any difference?
I like the idea of the studs and the special nuts look very aerospace which I am sure they are! As for con-rod bolts I used to buy 1300HF ones from Cavalitto - they weren't too expensive and at least for the 1600 Lancia said that the bolts must not be re-used, so I think you've been very wise - mind you I've got away with it for 28 years!
I'll try to post the exchanges on the blog if this rotten Internet connection ever works!
Regards
Paul
5.
I have run the engine for about 2000Kms with the brace but cannot say that there is a difference since many other parts were also modified and as I wrote in earlier mails the main bearings were found worn due dirt in the oil. That is all repaired now by grinding the crank to its first undersize and I'm now running the engine in again. But the gear box started to develop a massive oil leak last week coming from the prise shaft and this is another setback as the whole subframe assembly has to come down again in order to be able to remove the gearbox....
Keep you posted!
William
6.
Hello.
So it was dirt in the oil? I am surprised!
As for the gearbox, that of course is a common fault. The roller bearing and seal(s) are always a weak point - especially in the very early 'boxes which had only one seal.
The way I tackle the problem is to remove the engine, drain the 'box and remove the bell-housing; that way you don't have to drop the subframe - or worse, the gearbox!
Regards
Paul
7.
I do not have an engine hoist but I have a ramp so i think that removing the subrame altogether is less work and causes less risk for damaging something in the process.
The seal (double in this 1600 zagato box) is changed together with the bearing in 2006 just before the Lancia centenario in Turin. It functioned faultless for 7000kms.
Cheers,
William
8.
Yes I see.
Well, when I was fifteen years younger, my father had a Fulvia sedan. I changed his clutch in 3.5 hours - removing the engine - which is harder than on a coupé. Ah! those were the days!
I had forgotten that you had the same 'box as I. Those seals/bearings are a real pain!
Paul
The seal (double in this 1600 zagato box) is changed together with the bearing in 2006 just before the Lancia centenario in Turin. It functioned faultless for 7000kms.
Cheers,
William
8.
Yes I see.
Well, when I was fifteen years younger, my father had a Fulvia sedan. I changed his clutch in 3.5 hours - removing the engine - which is harder than on a coupé. Ah! those were the days!
I had forgotten that you had the same 'box as I. Those seals/bearings are a real pain!
Paul
