Discussion
You'll find all sorts of attempts to balance it. . . not sur eon the stamped number, as from what I've seen it's not that specific.
The backing plate often has pieces of threaded bar welded into the rolled edge to act as balancing weights along with the back of the damper being drilled to compensate aswell.
The whole bottom of the engine is balanced together, so changing the front damper/backing plate is a real issue.
The backing plate often has pieces of threaded bar welded into the rolled edge to act as balancing weights along with the back of the damper being drilled to compensate aswell.
The whole bottom of the engine is balanced together, so changing the front damper/backing plate is a real issue.
This has been covered a number of times . . . Ballistic Banana did a good write up which may be on the Griffith Pages . com.
I don't think it's so much of an issue with engines other than the 500's, where the use of the backing plate and welds isn't as common.
It also depends on which 36 tooth trigger wheel you're going for. There are more choices available since I did mine, as I've got the John Eales one with sensor bracket, but my engine is properly balanced. Trigger Wheels . com may now do a revised lighter weight one and i think others have used Ford items.
I wasn't aware that anyone could balance you up a pulley, not with great accuracy at least, but apparently Dom can do it, so worth pursuing that perhaps. . . . I certainly wouldn't just bolt something on and hope . . .
I don't think it's so much of an issue with engines other than the 500's, where the use of the backing plate and welds isn't as common.
It also depends on which 36 tooth trigger wheel you're going for. There are more choices available since I did mine, as I've got the John Eales one with sensor bracket, but my engine is properly balanced. Trigger Wheels . com may now do a revised lighter weight one and i think others have used Ford items.
I wasn't aware that anyone could balance you up a pulley, not with great accuracy at least, but apparently Dom can do it, so worth pursuing that perhaps. . . . I certainly wouldn't just bolt something on and hope . . .
Pink_Floyd said:
Johno said:
The whole bottom of the engine is balanced together, so changing the front damper/backing plate is a real issue.
How big a problem is this. I want to add a 36-1 toothed wheel to the pulley for an after market ECU, is this likely to upset things.I think that on my pulley, there are a couple of drill holes that look like they were to remove metal for balancing purposes. Could this be the case?
Johno said:
This has been covered a number of times . . . Ballistic Banana did a good write up which may be on the Griffith Pages . com.
I don't think it's so much of an issue with engines other than the 500's, where the use of the backing plate and welds isn't as common.
It also depends on which 36 tooth trigger wheel you're going for. There are more choices available since I did mine, as I've got the John Eales one with sensor bracket, but my engine is properly balanced. Trigger Wheels . com may now do a revised lighter weight one and i think others have used Ford items.
I wasn't aware that anyone could balance you up a pulley, not with great accuracy at least, but apparently Dom can do it, so worth pursuing that perhaps. . . . I certainly wouldn't just bolt something on and hope . . .
Was planning on machining down the original balance wheel on a lathe to account for the thickness of the trigger wheel (which is about 5mm). If I machined the opposite side of the pulley from where the drill holes are, would you consider this ok, or would the whole assembly need re balancing?I don't think it's so much of an issue with engines other than the 500's, where the use of the backing plate and welds isn't as common.
It also depends on which 36 tooth trigger wheel you're going for. There are more choices available since I did mine, as I've got the John Eales one with sensor bracket, but my engine is properly balanced. Trigger Wheels . com may now do a revised lighter weight one and i think others have used Ford items.
I wasn't aware that anyone could balance you up a pulley, not with great accuracy at least, but apparently Dom can do it, so worth pursuing that perhaps. . . . I certainly wouldn't just bolt something on and hope . . .
The crank is balanced externally, that is by using weights on the pulley and flywheel In an ideal world ( or a properly built engine ) the crank and rods are internally balanced and a “zero balanced” pulley is used. In addition to the actual balance weights the pulley has a harmonic damper attached ,which is a mass suspended on a slightly flexible (rubber) bit.
What I can say from experience is when the crank snaps it makes a fairly large bang and the engine sounds lather less than happy afterwards, followed by a less than happy but lighter wallet.
What I can say from experience is when the crank snaps it makes a fairly large bang and the engine sounds lather less than happy afterwards, followed by a less than happy but lighter wallet.
Here's a couple of shots for you from BB's pulley assembly. You'll note it is in 3 parts.
Front pulley
Damper
Backing plate
This is then a photo of the backinng plate, and although not that clear you will not on the bottom right there is an aberation in the curled edge. This is the TVR balance weight, or welded on bit of threaded bar, for those that haven't seen one up close yet
As I said earlier, this is generally always found on the 500's but not as prevalent from my understanding on the 4ltr derivatives. When you remove it you'll find other drill holes on the front or rear, so again you may need to check before adding anything to it.
According to Steve the number plate refers to the crank or the balance weight, not sure which, but perhaps Steve can help out here?
Here's a shot of my unit, you can not see the trigger wheel unfortunately as I have a John Eales damper and trigger wheel. The damper is slightly larger than OEM one, but it shows you the JE sensor and bracket you get with the kit. I slightly modded mine to get a fit I was totally happy with, but that just involved a file and 10mins.
I certainly wouldn't machine down the damper. If you don't have the backing plate you should have plenty of space to add a trigger wheel and I would probably look at a triggers wheels one as they are pressed plate rather than cast/machined and are unlikely to cause balance issues, but again I wouldn't do it without checking with someone like Dom, V8D etc . .
If it is a 500 then email Ballistic Banana as he overcame it and I don't want to suggest the method he used and then you have issues if you see what I mean, but it is surmountable.
Front pulley
Damper
Backing plate
This is then a photo of the backinng plate, and although not that clear you will not on the bottom right there is an aberation in the curled edge. This is the TVR balance weight, or welded on bit of threaded bar, for those that haven't seen one up close yet
As I said earlier, this is generally always found on the 500's but not as prevalent from my understanding on the 4ltr derivatives. When you remove it you'll find other drill holes on the front or rear, so again you may need to check before adding anything to it.
According to Steve the number plate refers to the crank or the balance weight, not sure which, but perhaps Steve can help out here?
Here's a shot of my unit, you can not see the trigger wheel unfortunately as I have a John Eales damper and trigger wheel. The damper is slightly larger than OEM one, but it shows you the JE sensor and bracket you get with the kit. I slightly modded mine to get a fit I was totally happy with, but that just involved a file and 10mins.
I certainly wouldn't machine down the damper. If you don't have the backing plate you should have plenty of space to add a trigger wheel and I would probably look at a triggers wheels one as they are pressed plate rather than cast/machined and are unlikely to cause balance issues, but again I wouldn't do it without checking with someone like Dom, V8D etc . .
If it is a 500 then email Ballistic Banana as he overcame it and I don't want to suggest the method he used and then you have issues if you see what I mean, but it is surmountable.
Many thanks for posting the pics. that really clears things up.
I bought a second pulley wheel and damper so I could make the modifications without having the car off the road, but the assembly doesn't look quite like yours - don't have it to hand, but it definitely doesn't have the weights added.
Not sure how your trigger wheel works from the photos, but I do have the Trigger Wheels wheel, it's about 5mm thick, not pressed. (I read transit vans use a pressed wheel which could fit). What I'm still not sure about is, if my trigger wheel is 5mm thick, where could it be mounted without removing metal to make way for it- and still keep the pulley in line with the belt?
I bought a second pulley wheel and damper so I could make the modifications without having the car off the road, but the assembly doesn't look quite like yours - don't have it to hand, but it definitely doesn't have the weights added.
Not sure how your trigger wheel works from the photos, but I do have the Trigger Wheels wheel, it's about 5mm thick, not pressed. (I read transit vans use a pressed wheel which could fit). What I'm still not sure about is, if my trigger wheel is 5mm thick, where could it be mounted without removing metal to make way for it- and still keep the pulley in line with the belt?
You can't see mine as it is obscured by the damper. You have to find a way to attach to the back of the damper, but
I can't advice you how exactly . .
With BB's set up he was ablw to sandwich the TW between the back plate and the damper, but without a backplate I an only suggest you use a similar munting technique to the ne in the pictures. Are there available holes in the damper? An you use the bolts for the front pulley?
You're best emailing BB as his set up is more like yours where as mine is JE damper and trigger wheel.
I can't advice you how exactly . .
With BB's set up he was ablw to sandwich the TW between the back plate and the damper, but without a backplate I an only suggest you use a similar munting technique to the ne in the pictures. Are there available holes in the damper? An you use the bolts for the front pulley?
You're best emailing BB as his set up is more like yours where as mine is JE damper and trigger wheel.
With most of our Serpentine installations we fit the trigger wheel just behind the front pulley. This is a picture of the set-up on a Chimaera 450 engine in a Range-Rover Classic. This trigger wheel, bracket and sensor was from Trigger Wheels.
The Rover V8 has an externally balanced crank as standard but as long as you put the trigger wheel just behind the front pulley and put any damping assembly that you remove back on in exactly the same orientation (i.e.: mark the position, do not turn the engine and line up the marks during re-assembly), you should have no problems. We have done many installs on a wide range of Rover V8s and have yet to have a problem with balancing issues with the trigger wheel set-up.
www.lloydspecialistdevelopments.co.uk
The Rover V8 has an externally balanced crank as standard but as long as you put the trigger wheel just behind the front pulley and put any damping assembly that you remove back on in exactly the same orientation (i.e.: mark the position, do not turn the engine and line up the marks during re-assembly), you should have no problems. We have done many installs on a wide range of Rover V8s and have yet to have a problem with balancing issues with the trigger wheel set-up.
www.lloydspecialistdevelopments.co.uk
Edited by drlloyd on Wednesday 3rd February 09:37
Edited by drlloyd on Wednesday 3rd February 09:53
drlloyd said:
..as long as you put the trigger wheel just behind the front pulley and put any damping assembly that you remove back on in exactly the same orientation (i.e.: mark the position, do not turn the engine and line up the marks during re-assembly), you should have no problems.
I don't know what you are talking about the keyway means you cant make any mistakes. Not turning the engine sounds a load of b
ks to me?Hi Spend,
We are talking about removing the removable pulleys from the crank damper assembly and then fitting the trigger wheel between the crank damper and the pulleys. These pulleys are retained by 6x 5/16th UNF bolts holding them to the damper assembly. The dowel location (roll) pin is then carefully removed before the trigger wheel and pulley rims are refitted. The marks ensure that the damper assembly is placed in the orientation that it was originally balanced in. These are re-torqued upon installation to 28NM.
As qualified and experienced aerospace and automotive engineers with many years experience with Rover V8s, we usually talk bks!! 
Just trying to be helpful.
www.lloydspecialistdevelopments.co.uk
We are talking about removing the removable pulleys from the crank damper assembly and then fitting the trigger wheel between the crank damper and the pulleys. These pulleys are retained by 6x 5/16th UNF bolts holding them to the damper assembly. The dowel location (roll) pin is then carefully removed before the trigger wheel and pulley rims are refitted. The marks ensure that the damper assembly is placed in the orientation that it was originally balanced in. These are re-torqued upon installation to 28NM.
As qualified and experienced aerospace and automotive engineers with many years experience with Rover V8s, we usually talk b
ks!! Just trying to be helpful.
www.lloydspecialistdevelopments.co.uk
The pressed steel pulley is what he is refering to and that is not keyed, only the cast damper part - what he is suggesting is that if you seperate the 2 items theoretically the pressed part can be bolted back on in a different position. As you say, main damper part can only go on one way though.
By leaving the damper bolted in place, taking the pulley off and then doing a timing disc mod you could put the pulley back on wrong, particularly if you have not marked it up and turned the engine for any reason during the modification. Theoretically you would only mark pulley to damper so irrelivant if engine is turned but if you mark it differently, or not at all, then turning the engine could have some relevance to getting it back wrong.
By leaving the damper bolted in place, taking the pulley off and then doing a timing disc mod you could put the pulley back on wrong, particularly if you have not marked it up and turned the engine for any reason during the modification. Theoretically you would only mark pulley to damper so irrelivant if engine is turned but if you mark it differently, or not at all, then turning the engine could have some relevance to getting it back wrong.
Edited by JKY on Wednesday 3rd February 16:02
Except there is the locating pin / dowel that makes re-alignment pretty foolproof.... even if you have the assembly apart?
If you sandwich the TW, just drill it so the pin goes through it. I'm pretty sure on all versions the assembly is fixed on the crank woodruff key and the assembly is fixed together by the rolled steel press pin/dowel so the whole lot can't be fked by up by anyone.
If you sandwich the TW, just drill it so the pin goes through it. I'm pretty sure on all versions the assembly is fixed on the crank woodruff key and the assembly is fixed together by the rolled steel press pin/dowel so the whole lot can't be f
ked by up by anyone.grlloyd specifically mentioned about removing the pin to fit the trigger wheel and hence the posibility of getting it back wrong.
Spend you are correct though, if the pin is left in, trigger wheel drilled, and then all bolted back then you cannot get it wrong.
Anyhow, it appears that, per the main reason for this thread, the pulleys seem balanced to each engine and problems could arise by swapping or modifying.
Spend you are correct though, if the pin is left in, trigger wheel drilled, and then all bolted back then you cannot get it wrong.
Anyhow, it appears that, per the main reason for this thread, the pulleys seem balanced to each engine and problems could arise by swapping or modifying.
Edited by JKY on Wednesday 3rd February 16:39
Edited by JKY on Wednesday 3rd February 16:40
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