Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > 700/900 Series General
Register Members CarsBlogs Help Calendar Mark Forums Read

Notices

700/900 Series General Forum for the Volvo 740, 760, 780, 940, 960 & S/V90 cars

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

Timing belt tensioner failure

Views : 422

Replies : 18

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Feb 19th, 2019, 12:51   #11
Stephen Edwin
Learning as best I can
 

Last Online: Yesterday 21:56
Join Date: Jun 2010
Location: Thurrock
Default

Quote:
Originally Posted by monty400k View Post
looks like the key on the crank sheared off so the bottom pulley is spinning, hoping it's on the pulley and not the crank as i've got a spare one, otherwise it'll be time for another engine.

ouch !!!


.
Stephen Edwin is offline   Reply With Quote
Old Feb 19th, 2019, 14:05   #12
TonyS9
Premier Member
 

Last Online: Yesterday 17:08
Join Date: Jul 2009
Location: Holywood
Default

Is the middle bit separated from the outer (rubber moulded connection)?

Otherwise the Bolt should be tight enough to not rely on the key. If the bolt is missing or loosened, it means it wasn't assembled correctly.

It needs a big torque and something to properly hold the crank solid. Possibly they just tightened it until the engine turned, maybe held it by hand. That is only about 1/4 of the torque needed.

Edit to say - sorry I'm talking about red block, not sure about 6 cyl.

Last edited by TonyS9; Feb 19th, 2019 at 14:11. Reason: wrong engine
TonyS9 is offline   Reply With Quote
The Following 2 Users Say Thank You to TonyS9 For This Useful Post:
Old Feb 19th, 2019, 14:06   #13
360beast
I'm addicted to my 360
 
360beast's Avatar
 

Last Online: Today 09:21
Join Date: Feb 2012
Location: UK
Default

Sounds like they didn't know what they were doing all along!
360beast is online now   Reply With Quote
The Following 2 Users Say Thank You to 360beast For This Useful Post:
Old Feb 19th, 2019, 20:35   #14
Laird Scooby
Premier Member
 
Laird Scooby's Avatar
 

Last Online: Today 09:37
Join Date: May 2012
Location: Lakenheath
Default

The key between pulley and shaft is meant to be a form of mechanical fuse so it breaks if the torque rquired to turn whatever is being driven exceeds safe limits.
Two possibilities here, one the key was old and weak and just gave up the ghost. Two is that they didn't replace it, or if they did, it failed prematurely for some reason.

Either way, you need to get them to look at what caused the key to fail. If they set the crank 90 degree BTDC so the pistons are halfway down the bores, can the camshafts be turned easily? I think (although not 100% sure) there is an oil pressure restrictor valve in the top of the block. If this has failed, it will starve the camshaft bearings of oil causing siezure. If this has happened it's a head off job.

Think you said it was a replacement engine from somewhere? Was the oil and filter changed when it was fitted? Negelected oil and filter changes can cause those oil restrictor valves to block/fail.

Needs these basics checking out before they start replacing the keys and pulleys and whatever else and potentially turning the valves into bananas.
__________________
Cheers

Dave

Next Door to Top-Gun with a Rover 827 Sterling and a 765 GLEa V6!
Laird Scooby is online now   Reply With Quote
The Following User Says Thank You to Laird Scooby For This Useful Post:
Old Feb 19th, 2019, 21:34   #15
monty400k
Member
 

Last Online: Yesterday 21:51
Join Date: Aug 2012
Location: Glasgow
Default

Engine came out of my previous 960, had the head rebuilt 3 years ago as the valve stem seals had gone, regular oil changes, up to this point it was perfect
monty400k is offline   Reply With Quote
The Following User Says Thank You to monty400k For This Useful Post:
Old Feb 19th, 2019, 21:56   #16
Piet22
Junior Member
 

Last Online: Mar 18th, 2019 23:12
Join Date: Sep 2008
Location: Amsterdam
Default

It is not uncommon for a timing belt to slip a few teeth while parking on a steep hill. The reason is that the tensioner cannot handle a backwards rotating engine very well. It is therefore recommended to park in reverse if you are facing uphill and in 1st if you are facing down hill.

Piet
Piet22 is offline   Reply With Quote
The Following 2 Users Say Thank You to Piet22 For This Useful Post:
Old Feb 20th, 2019, 19:46   #17
monty400k
Member
 

Last Online: Yesterday 21:51
Join Date: Aug 2012
Location: Glasgow
Default

Update, garage removed the crank pulley and it was good as new, out of options they took the head off, all good there too, valves look to be fine, however when they try to wind the engine over on the crank there is several points of resistance so it looks like it has spun a shell so engine is scrap.

Ive got the 2.5 that came out of the car that could probably be refitted although it wasn't running that well when I got it, I suspect the head gasket, wish Id done a compression check before taking it out, Ive got a 2.8 low compression engine that Id set aside to turbo charge at some point although this would not be a quick solution. I could source another 3.0, either way its probably going to cost me more than Im willing to spend and I need transport so it looks like Ill cut my losses and break it
monty400k is offline   Reply With Quote
The Following 2 Users Say Thank You to monty400k For This Useful Post:
Old Feb 20th, 2019, 21:22   #18
Laird Scooby
Premier Member
 
Laird Scooby's Avatar
 

Last Online: Today 09:37
Join Date: May 2012
Location: Lakenheath
Default

What a bummer! Two possible suggestions, strip the 2.5 and rebuild it with a new head set, fit it and keep it as a known good runner (after the head gasket it should be, especially if you get the head checked/skimmed) or simply refit the 2.5 and flog it before anything else goes wrong!
__________________
Cheers

Dave

Next Door to Top-Gun with a Rover 827 Sterling and a 765 GLEa V6!
Laird Scooby is online now   Reply With Quote
The Following User Says Thank You to Laird Scooby For This Useful Post:
Old Feb 28th, 2019, 19:18   #19
rwdkev
VOC member
 

Last Online: Mar 18th, 2019 17:22
Join Date: Apr 2013
Location: Dudley
Default

Quote:
Originally Posted by Stephen Edwin View Post
Does the belt on this engine need re-tensioning after a "running in" mileage? If so. Was that done?
Tensioner on all white blocks is automatic. Hydraulic aspect is for damping, not the actual tensioning function.
rwdkev is offline   Reply With Quote
The Following User Says Thank You to rwdkev For This Useful Post:
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 10:11.


Powered by vBulletin
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.