+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: The problems never end (/showthread.php?tid=5098)
RE: The problems never end - Steve Jones - 18-10-2020
Not a bodge as such but a repair to an insignificant issue that caused more damage than the issue it was trying to repair!
Rear lower crankcase corner and a 'Tinker's Patch' has been made in copper and fitted with a series of 2BA screws. Behind the patch is a small area of corrosion to the casting where, perhaps, it had been affected by water. No associated damage on the inside of the crankcase so the defect was only cosmetic. However, the drillings for the 2BA screws had produced a series of 10 small holes through the side of the case!! Given that this was the only issue with an otherwise excellent vintage, sand cast, crankcase a repair was required comprising the sealing of the holes with suitable tight fitting aluminium rivets (thanks for the suggestion and the rivets, Duncan) with a dab of stud lock on each as belt and braces.
Steve
RE: The problems never end - Colin Swinbourne - 18-10-2020
Scored bores ...I feel your pain!
My 1929 Rover had been running rough and was very oily...valve guides - no problem, off with its head only to discover deep tramlines down no 1 & 2 cylinders ☹️ The gudgeon pin circlips had failed (actually I don’t think they were ever fitted correctly as 3 and 4 were on their way!
Re-sleeved and rebore.
Unfortunately your real opinion is either another block or sleeve and rebore.
RE: The problems never end - 12jslater - 18-10-2020
Is there any way of filling the deep gouges on the cylinder walls, I've calmed down now from my swearing and kicking haha, the car might be kept for a while longer yet.
As I don't have ANY money to spare on having it sleeved, I barely had enough spare from my current part time job to buy the gasket set haha.
Maybe brazing it then somehow getting level again?
RE: The problems never end - Alan - 18-10-2020
If money is an object- in the 70s when I had no money to spare I had a gudgeon pin work loose and seriously scored the bores. Acting on the advice of a very well respected Seven engine fettler, I replaced the errant con rod but left the bore alone. That engine went on to run in countless trials and the odd circuit race. I never noticed an oiling problem and only swapped it because I’d built a big valve block I wanted to use. What I’m saying is don’t worry too much. Find out what is is, fix the rings or the con rod. But, it should be fine.
RE: The problems never end - Charles P - 18-10-2020
(18-10-2020, 06:54 PM)Alan Wrote: If money is an object- in the 70s when I had no money to spare I had a gudgeon pin work loose and seriously scored the bores. Acting on the advice of a very well respected Seven engine fettler, I replaced the errant con rod but left the bore alone. That engine went on to run in countless trials and the odd circuit race. I never noticed an oiling problem and only swapped it because I’d built a big valve block I wanted to use. What I’m saying is don’t worry too much. Find out what is is, fix the rings or the con rod. But, it should be fine.
Let me align with Alan here.
The compression is good, it doesn't burn oil so the bore isn't the issue. Don't worry about it.
However a rogue gudgeon pin needs dealing with.
It'll either be a small end clamp bolt or circlips/end pads. Fix these (trivial) and put it back together. If by chance the rod is knackered at the small end, a replacement rod may be needed. Again, not living hell, especially as I think you have a Big 7 which must have shells not white metal.
Charles
c
RE: The problems never end - Howard Wright - 18-10-2020
Hi Charles
It’s a good call and can the piston con rod be pulled up through the bore on a big seven? If so simply a question of dropping the sump, unbolting number 2 big end and pulling the piston up.
Cheers
Howard
RE: The problems never end - Bob Culver - 18-10-2020
Hi Tony
That is quite the most ingenious solution to the tinkle. It used to be very much characteristic of Sevens and as a small boy I can recall being able to distinguish them without looking.
RE: The problems never end - Greig Smith - 18-10-2020
Drain & pull the oil pan off, pop the offending piston out the top & have a quick look at the gudgeon pin & the rings & the little end bolts as the brains trust have suggested - these guys know their stuff & have helped me tremendously.
You can do this over an evening, won't cost you anything except a bit of sweat equity. Post some pictures of what you find. Many engines will run happily on a scuff or two. I know of a 1300 Alfa twin cam that ran for 8000+ miles before the motor came apart for an unrelated issue - turns out the previous owner forgot the circlips for the gudgeon pins on all 4 pistons..... It also had completed a 1000 mile cross country journey in 2 days. I've seen the barrels, they were not bad and the owner recycled them into a 1400cc upgrade.
Bottom line your engine will probably run for miles with a scuff or two, but not if you ignore it now.
Aye
Greig
RE: The problems never end - Ruairidh Dunford - 18-10-2020
As others had said - A7 engines can run quite happily for many years with scores in the bores, provided you fix whatever has caused the marks in the first place.
We have all been where you were today - some of us more times than others - it soon passes, once the car is up and running and you are enjoying what it really has to offer.
Keep that goal in sight and don't be afraid to stop, stand back and take stock.
RE: The problems never end - Brettfcars - 19-10-2020
Great advice has given by others to check the gudgeon pin is firmly fixed, if the scores are in line with the crankshaft.
As for bodges, I removed this fan from a purchased “ told running” engine due to a riveted repair !
And then found it in more pieces the next day after leaving it untouched on my work top.
An accident just waiting to happen.
Brett