Changing a cam belt .. - Alfa Romeo Forum
You are currently unregistered, register for more features.    
 3Likes
  • 2 Post By gazza82
  • 1 Post By Pud237
 
Thread Tools
(Post Link) post #1 of 16 Old 23-11-15 Thread Starter
Status: SOLD my 156!
AO Gold Member
 
gazza82's Avatar
 
Join Date: Jan 2003
Location: United Kingdom
County: Buckinghamshire
Posts: 9,063
Changing a cam belt ..

Now I know there is a right way (cam locks, dti, tensioner tools) and there are the work ways (most involve Tippex) , but what about a third-way?

On Car SOS recently, Fuzz replaced the cam belt on a Nissan Skyline R33.

He did it by cutting the belt lengthwise while on the car and removing the outer half. Then he fitted the new belt onto the various gears. He then cut off and pulled out the rear half of the old one. Then pushed the new belt fully on. His view was it then was timed the same way and nothing had moved. Which I guess I have to agree with.

I had my doubts as (1) was the engine timed properly to start with (but I would hazard a guess he had checked but that's boring TV) and (2) wasn't sure how he got it past any tensioners (again boring TV) but am not familiar with a straight six Nissan Skyline lump.

So the question is "would you" try this on your Alfa ??? Or should that be have you?
mapalfa and Be chino lupo like this.

cheers, Gary

HIS: ex-1998 156 2.0 TSpark with Sport Pack 2, sunroof and hi-level spoiler in Alfa Rosso. V6 intake mod, clear side repeaters and Zeatek undertray. 10th Sep 1998 to 12th Jan 2017

HERS: 2009 MiTo 1.4 95bhp Turismo arrived 21st November in Techno Grey with colour-coded headlight surrounds.

My Alfa156 Web Site - how-to's, piccies, links, useful stuff, etc.
gazza82 is offline  
Sponsored Links
Advertisement
 
Status: Still raining
AO Member
 
mapalfa's Avatar
 
Join Date: May 2008
County: Pembrokeshire
Posts: 316

Member car:

2008 Brera 2.4

Interesting idea.

I'm not sure I want to be the first one to try it though.
mapalfa is offline  
Status: zzzzzzzz
AO Platinum Member
 
symon's Avatar
 
Join Date: Dec 2005
Location: United Kingdom
County: Oxfordshire
Posts: 36,943
Bodge job.
symon is offline  
Status: -
AO Silver Member
 
Chris155's Avatar
 
Join Date: Jan 2014
Location: United Kingdom
County: Cheshire
Posts: 2,963
It's a suggestion that has been put forward here and on 156.net before now, usually in relation to the v6's. As you say, you're assuming that the engine is timed correctly to begin with in the first instance.

I can't see how you could do it by backing the tensioner off, the belt would have to be in tension to keep everything timed up correctly. So fitting a new belt would be a right pain in the asre on a transverse engine.

Also In the case of the v6 (and the t-sparks etc) it would be pointless as you can't replace the tensioner using this method. And that's the bit that fails first...
Chris155 is offline  
Status: -
AO Silver Member
 
Chris155's Avatar
 
Join Date: Jan 2014
Location: United Kingdom
County: Cheshire
Posts: 2,963
And then there's the issues with the water pumps...
Chris155 is offline  
rxe
Status: Busso
AO Silver Member
 
Join Date: Apr 2012
Location: United Kingdom
County: Berkshire
Posts: 4,086
Don't really see the point in bodging it when the correct tools cost less than £100. If you get it fractionally wrong, you'll spend more than £100 on wasted petrol over the life of the belt. If you get it very wrong, you need a new engine.
rxe is offline  
Status: -
AO Platinum Member
 
Ralf S.'s Avatar
 
Join Date: Feb 2002
Location: The land that Time forgot
Posts: 13,058
The cam locks are relatively cheap (i.e. they'll pay for themselves the first time you use them). It's a no-brainer to do it properly..

Ralf S.
Ralf S. is offline  
Status: #keepFightingMichael
AO Gold Member
 
EauRouge's Avatar
 
Join Date: Jun 2009
Location: Suriname
County: Brokopondo
Posts: 7,703
I wouldn't, I would always want camshafts locked solid at TDC, you would be amazed at how much sprockets move when fiddling around this area.
EauRouge is offline  
Status: V6 Inside
AO Silver Member
 
ransoman's Avatar
 
Join Date: Jan 2007
Location: United Kingdom
County: Aberdeenshire
Posts: 4,881
I would find it harder and more effort to cut the belt so accurately TBH.

The correct tools are not expensive and not hard to use.
ransoman is offline  
(Post Link) post #10 of 16 Old 01-12-15 Thread Starter
Status: SOLD my 156!
AO Gold Member
 
gazza82's Avatar
 
Join Date: Jan 2003
Location: United Kingdom
County: Buckinghamshire
Posts: 9,063
Thanks all ...

I just wondered ... I have the cam locks so I'd do it the proper way .. but as with all TV programmes they don't show you EXACTLY how to do it and also not what he did BEFORE hand to make sure it was properly timed in.

I couldn't see them just trying as the engine wouldn't run .. and one of the first things we all would do it to check the belts and timing was right ... before looking for bent valves! In the end I think it was a cam timing unit .. it had "might not work" written on it in felt-pen!
gazza82 is offline  
Status: V6 Inside
AO Silver Member
 
ransoman's Avatar
 
Join Date: Jan 2007
Location: United Kingdom
County: Aberdeenshire
Posts: 4,881
They most likely didn't check. Only way to check is to set the engine to the reference marks and of course Alfa's don't have them because the pulley's aren't keyed to the camshaft, that is Why you have to use the timing tools.

Even worse on the TS as you don't have a top dead center mark. you have to fanny around with a dti guage instead.
ransoman is offline  
Status: zzzzzzzz
AO Platinum Member
 
symon's Avatar
 
Join Date: Dec 2005
Location: United Kingdom
County: Oxfordshire
Posts: 36,943
Quote:
Originally Posted by ransoman View Post
They most likely didn't check. Only way to check is to set the engine to the reference marks and of course Alfa's don't have them because the pulley's aren't keyed to the camshaft, that is Why you have to use the timing tools.

Even worse on the TS as you don't have a top dead center mark. you have to fanny around with a dti guage instead.
The TS does have a TDC mark.

It is on the crank pulley, and lines up with the mark on the lower cover.

After having done a few I think it is much more accurate than messing about with a DTI due to the dwell at TDC.
symon is offline  
Status: Busy busy busy!
Club Member
Membro Premio
 
Pud237's Avatar
 
Club Member Number: 71
Join Date: Apr 2006
Location: United Kingdom
County: Cumbria
Posts: 44,753
Next time I have a Twinspark apart I will see if the diesel crank locking tool fits. It fits the 1750 TBI as well as all the diesels 8v/16v/10v/20v so maybe it will fit a TS too as they are all so similar. Then I can check with a DTI whether it is actually at TDC or not with the tool fitted. I do prefer having the crank locked than using a DTI. Especially on the V6 as it is so easy for it to move itself away from TDC.
Pud237 is offline  
Status: Busy busy busy!
Club Member
Membro Premio
 
Pud237's Avatar
 
Club Member Number: 71
Join Date: Apr 2006
Location: United Kingdom
County: Cumbria
Posts: 44,753
Just doing a GTA belt today - noticed tippex on the pulleys before I started

Both inlet cams perfect, rear bank exhaust cam about 1.5, maybe 2 teeth out. Front bank exhaust cam a tooth out. The tippex marks were a great visual aid to show how far out the timing was

Just goes to show, either it wasn't correctly timed when they started the job (and they maintained that bad timing), or it was correctly timed before they changed the belt, and without the pulleys cracked off when they first turned the engine the tension evened out and the cams all moved relative to one another and the crank. You just can't say for sure which scenario it was.
maxiboy wales likes this.

Autolusso Penrith - UK's leading independent Alfa Romeo specialist with branches in Bedfordshire, Cumbria & Dorset

Wizard Exhaust systems available here

Tel: 01768 879 171
Pud237 is offline  
Status: We did it... Now a brighter future
AO Member
 
Sam bailey's Avatar
 
Join Date: Jul 2014
Location: United Kingdom
County: Kent
Posts: 800

Member car:

05 156v6 veloce

I havent done it the tippex way on my v6 but ive done it on fords and vauxhalls before but those cars i really didnt care about..
Sam bailey is offline  
(Post Link) post #16 of 16 Old 22-01-16 Thread Starter
Status: SOLD my 156!
AO Gold Member
 
gazza82's Avatar
 
Join Date: Jan 2003
Location: United Kingdom
County: Buckinghamshire
Posts: 9,063
Mine's got tippex marks ... they are actually quite accurate so may have been when the engine was rebuilt to put it back almost in the right place so save time.

Having changed the cam belts twice now in a few months (1st time routine, 2nd time head gasket) the fear has gone ... the balance belt was a pain though and I don't think I did it right first time.

But my TS is so smooth now .. I'm sure it hasn't been this smooth ever .. I have to be very careful when overtaking and at just under 70 Or it's 85 in seconds .. (must check this as the road-test says 11 secs for 70-90 in 5th .. I'm sure it's quicker than that! Only difference is I have the 2.5 V6 intake and a powerflow air filter .. plus my engine is fully run in (at nearly 206k!) )


Now to get rid of the clunking suspension (A/R bar) and exhaust that is touching the rear A/R bar again ...
gazza82 is offline  
Reply

Go Back   Alfa Romeo Forum > Supported Alfa Romeo Models > Technical & Vehicle Assistance > Engines (TS, JTS, JTD & V6)

Tags
belt , cam , changing

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome