Alfa Romeo Forum banner

146 big end bearings

1K views 11 replies 5 participants last post by  Smaky 
#1 ·
Hi all, I'm back with another broken Ti. I've picked up a V reg with knackered big end bearings. The owner has told me that it started knocking on the motorway, he took it straight to the alfashop which is only 5 miles away. I think this is genuine as he had several receipts for other work on the car. They diagnosed it, quoted him and he left the car there until he could afford the work. He obviously decided not to go ahead, as I saw it on ebay last month, viewed it, and paid £300 as seen. In black too! Phwoar! I collected it from the garage and trailered it back to mine.
You know what I'm going to ask next don't you?
Is there any reason, if I get the car on a lift, that this job can't be done with the engine in situ?
The guy at the alfashop told me that if the engine was nursed straight to a garage, the crank should have survived any scoring. I have run the car only to get it off the trailer, and it started fine, ticked over but was obviously knocking loudly.
I dunno, I think I'm up for a bit of this...
Any help as always greatly appreciated.
 
#2 ·
I am pretty sure the job can be done from underneath. However i wouldn't hold my breath on the crank being ok if the car was driven for 5 miles with it knocking.

The crank can also twist out of true as well as score if it is run with knocking big ends.

You won't know for sure until you get it apart though.
Also if the big ends have become damaged due to low oil there can be other problems throughout the engine such as camshafts loosing lobes.
Most people recommend replacing the oil pump, as this may also become damaged by the low oil level, and you don't want your new bearings failing as well.
 
#3 ·
thanks for that. well, maybe it'll be ok, maybe it won't. will definitely change the oil pump as well. i have another healthy engine in the (cat D write off) red 146 i've been building for the trackday thing, so if all else fails i could swop the two. it's not ideal though as then the red one will be engineless! still, for what the new car cost, i'm going to give it a go. I guess this means that now I'm officially an alfaholic. off with it's sump!
 
#4 · (Edited by Moderator)
I have run the car only to get it off the trailer, and it started fine, ticked over but was obviously knocking loudly.
If it is “knocking loudly” at tick-over it will be to far gone and the crank will be damaged, you may be luck enough to not have done too much damage and be able to get the crank ground.

IMO you will be wasting your time and money putting in a set of shells.

Ned
 
#10 ·
IMO you will be wasting your time and money putting in a set of shells.

Ned
I don't, as long as the crank is fine you can go ahead and do the work at home, jack up the car, and be able to support the diff when you take out the rear engine mount, the rest is easy to get to the shells, down pipe and sump off then simply remove the bearing caps from the rods.
 
#5 ·
it didn't actually knock at tickover, I should have made that clearer. It knocked when raising the revs just enough to move the car in the way it had to be, which was probably more like 2-2500 rpm. It has been run for no more than a minute since I took ownership. I'm getting conflicting views, which is good I guess. Alfashop man said 'new shells should be ok' but recommended I either did it myself or found a good local mechanic, as his workshop would charge a fortune. He also 'doubted' that the crank would be knackered, and obviously knew some of the car's history. Others saying 'phh, good luck mate' accompanied by various eye-rolling based facial expressions. Local mechanic is happy to do it, has good alfa experience but unfortunately can't do it for at least two months and would want it for a month as well!
 
#6 ·
So, anyone else had this scenario? Must say I'm a little underwhelmed by the replies guys, I know I'm not an forum veteran, but it's nice to hear several opinions! I'm sure someone on this list has undertaken exactly this task, or would I get a better response if I post in a different forum on this site? Thanks to Ned and Symonh2000 for their help, but I'm not feeling the Alfa love in full effect yet:)
 
#8 ·
I'm picking up one with a similar problem this weekend. Luckily though a friend of mine owns an alfa garage and we already have a crank and some new shells. The guy wants £200 for the car (I only really want it for the leather interior for mine) but the guy sounds genuine when he said its only just started knocking and hasnt been moved since. Only time will tell :thumbs:
 
#11 ·
On the car I'm picking up sunday I'm not entirely sure if the crank is fine or not. Now we already have a new crank and shells but if we end up just doing a re-grind we have been quoted £100 for the grind and shells to match (from someone we know). Worth it imo :thumbs:
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top