Big end failed

Ask and give advice here
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Big end failed

Post by Vintage man »

Today driving my 1600 tp bus it last all power then locked up, stripped the engine and found that only one big end ran a bearing. The bearing pushed out on the sidesWhy would the happen and could over heating have caused it. What would go first if it did over heat. Thanks in advance as it is really bugging me.Could overheating cause this without damaging the piston and barrels.


User avatar
Tony Z
Donor
Donor
Posts: 14992
Joined: Wed Sep 14, 2005 8:33 am
What model do you have?: 2.3L 69; 1302; P/Van
Location: Klipheuwel (near Durbanville), Cape Town or working at sea
Has thanked: 191 times
Been thanked: 487 times
South Africa

Re: Big end failed

Post by Tony Z »

anything could have caused it, wrong oil, dirty oil, old oil, incorrect machining clearances, wrong bolt torque, knocking, wrong spark plugs, burning exhaust valve, wrong timing, not serviced often enough, broken down oil, petrol in oil, too low oil level, too high oil level, air in oil, oil without anti-foaming additives, over-revving, worn out block, bad luck...

overheating might have roasted the oil and caused this. Overheating might have been causing detonation and the first thing to give in was the big end
User avatar
retrovan
Donor
Donor
Posts: 8709
Joined: Mon Feb 07, 2011 8:51 pm
What model do you have?: 52T1,68FB,72Bay,75FL
Location: Eich! no, in Jefferys Bay
Has thanked: 421 times
Been thanked: 539 times
Contact:
Netherlands

Re: Big end failed

Post by retrovan »

You will have to give more detail on your engine.

Was it newly built, was it very old, did it have all the plates around the engine, was it serviced recently

Maybe a picture of the engine in the car before it happened would also help.

All these would change the prognosis.

Herman.
1952 Split Beetle 1835cc
1968 Fastback 2Lt.type4
1972 Low Light Bay Panel Van 2Lt type 4
1975 Fleetline Panel Van 1914cc
2020 MeFusco Beetle Truck 2Lt type 4
1972 FT Hahn SP 1776 cc
Dawie
Fuel Injection
Posts: 2110
Joined: Sat Sep 30, 2006 10:25 pm
What model do you have?: Aircooled, various
Location: Kaapstadt
Has thanked: 42 times
Been thanked: 207 times
South Africa

Re: Big end failed

Post by Dawie »

Did the oil pressure light come on before this happened?
Staying Aircooled is so much nicer.
Do'nt assume anything- (While doing fault-finding).
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Re: Big end failed

Post by Vintage man »

Will get some pictures ,no oil light but since the motor was fitted even after fresh oil and serviced the oil light came on fligering when hot at idle.It was a rebuilt engine.
Terry Phillips
Fuel Injection
Posts: 2005
Joined: Mon Jul 16, 2012 5:56 pm
What model do you have?: T3,1beetle
Location: Kempton Park
Has thanked: 193 times
Been thanked: 121 times
Zambia

Re: Big end failed

Post by Terry Phillips »

Who done the motor and how long ago was it done.
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Re: Big end failed

Post by Vintage man »

Not sure Terry but was standing for about 4 years before I fitted it.
Image

Image

Image

Image

Image

Image

Image

Image
User avatar
Tony Z
Donor
Donor
Posts: 14992
Joined: Wed Sep 14, 2005 8:33 am
What model do you have?: 2.3L 69; 1302; P/Van
Location: Klipheuwel (near Durbanville), Cape Town or working at sea
Has thanked: 191 times
Been thanked: 487 times
South Africa

Re: Big end failed

Post by Tony Z »

you've got compression leaks everywhere
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Re: Big end failed

Post by Vintage man »

Thanks Tony ,I did notice that the one side was hotter than the other side as the paint on the silencer was off compared to the right side.The exhaust also had a bit of leakage,Would it be a vacume leak that could cause this as the both sides would have been the same then,

When you say compression leaks , is that heads ,valves.
User avatar
Tony Z
Donor
Donor
Posts: 14992
Joined: Wed Sep 14, 2005 8:33 am
What model do you have?: 2.3L 69; 1302; P/Van
Location: Klipheuwel (near Durbanville), Cape Town or working at sea
Has thanked: 191 times
Been thanked: 487 times
South Africa

Re: Big end failed

Post by Tony Z »

yours are barrels to heads
bad machining and/or bad fitting is likely the cause
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Re: Big end failed

Post by Vintage man »

Image

Image

Image

Image

Image

Image

Image
Vintage man
Oil Pump
Posts: 280
Joined: Thu Apr 20, 2017 4:36 am
What model do you have?: 1976 bay window
Location: Roodeport
Has thanked: 51 times
Been thanked: 7 times

Re: Big end failed

Post by Vintage man »

Some pictures added and I see the conrod that seized is dry as the rest still wet with oil.
Cause ?
User avatar
retrovan
Donor
Donor
Posts: 8709
Joined: Mon Feb 07, 2011 8:51 pm
What model do you have?: 52T1,68FB,72Bay,75FL
Location: Eich! no, in Jefferys Bay
Has thanked: 421 times
Been thanked: 539 times
Contact:
Netherlands

Re: Big end failed

Post by retrovan »

It would seam as if you have a blocked oil port and or bad spring in your pressure release by-pass.

Some guys when rebuilding an engine, forget to flush the oil cooler and the old metal shavings block the oil passages when 1st starting the re-build motor

Please see these items and make sure where your problem is before making the same mistake again.

sorry that it happened, good luck

Herman
1952 Split Beetle 1835cc
1968 Fastback 2Lt.type4
1972 Low Light Bay Panel Van 2Lt type 4
1975 Fleetline Panel Van 1914cc
2020 MeFusco Beetle Truck 2Lt type 4
1972 FT Hahn SP 1776 cc
calooker
Donor
Donor
Posts: 4973
Joined: Wed Sep 14, 2005 9:24 am
What model do you have?: 77 SP
Location: Johannesburg
Has thanked: 4 times
Been thanked: 98 times
Contact:

Re: Big end failed

Post by calooker »

Vintage man wrote: Tue Oct 09, 2018 8:00 am Some pictures added and I see the conrod that seized is dry as the rest still wet with oil.
Cause ?
Its dry because it got so hot it burned all the oil off.
For what it's worth, ignorance has no limits ......
calooker
Donor
Donor
Posts: 4973
Joined: Wed Sep 14, 2005 9:24 am
What model do you have?: 77 SP
Location: Johannesburg
Has thanked: 4 times
Been thanked: 98 times
Contact:

Re: Big end failed

Post by calooker »

Vintage man wrote: Mon Oct 08, 2018 12:27 pm Will get some pictures ,no oil light but since the motor was fitted even after fresh oil and serviced the oil light came on fligering when hot at idle.It was a rebuilt engine.
If the motor blew and the light never came on tells me that you had a blockage in the oil passages as little or no oil got to the big end.
This leads to the rod end getting super hot to the point it will melt / fuse metals.
For what it's worth, ignorance has no limits ......
Post Reply