CVVT hub diagnosis

Agrector · Post by **Agrector** » 22 Nov 2018, 08:43

Hi Everyone!

Just found this topic today.

I guess I have the same problem on my 2004 Volvo V70 2.5T FWD. During the last service - oil change etc. - it was revealed that both of the cam gear is moving. With the serial number I only found the whole thing in one piece for high price. Is there any option to solve this problem, other than change the whole gear? For example is it possible that the gear itself remains the same and only chnaging the inside part or even a new seal can solve it? Or is it recommended to change everything together?

I just realized the problem at 107'700 miles - 173'397 kms - right now I have little above 120'000 miles - 193'200 kms - in the car. As far as I know it wasn't changed or repaired before. How long can I drive safely with this? I am just asking because I don't have enough money to change both the cam gears for a brand new - what I found costs 482$/cam gear.

Thanks for you help!

Post by **cn90** » 22 Nov 2018, 09:12

The VVT Hubs usually get loose around 150K.
There is an O-ring kit for sales on ebay but it does not fix the "wobble" issues.

The only option is a new VVT Hub.
You can buy a VVT Hub in the US for about US $250/each. The Exhaust VVT is different from the Intake VVT Hub.

More info here:

Large oil leak after replacing exhaust camshaft (cvvt) seal - help needed!
https://volvoforums.com/forum/volvo-xc9 ... ded-81251/

Post by **oragex** » 22 Nov 2018, 09:21

Do you mean the hubs have some lateral play? How much - how many mm approximately. Some play is not at all a problem.

There is also the possibility of the belt itself 'wobbling' over the cam gears, this is usually related to a tensioner problem (same thing when the belt runs near one edge of the hubs)

If you think replacing the hubs, real well how to mark them so as not to lose the timing advance (not the same thing as the marks when installing a new belt). A used similar hub without play in it is also a good option.

Agrector · Post by **Agrector** » 23 Nov 2018, 05:25

Thansk for the answers!
There is no sign around the hubs of oil leak, I guess it is good, but unfortrunately there is more play/wobble than it should be as far as I know it shouldn't be more than 2 mm. As checked with the engineer there marks aren't there where they should be, the belt cahnge has took place around 6-7 months ago, maybe they did something wrong, but for sure they didn't align the gears with the factory mark - I guess it makes problem too.
The backstory of my engine, after I bought it just realized there is a serious problem with the engine, so I just went back to the dealer, made a deal that he repairs the engine on his own cost - I guess he did as cheap as possible.
Other than that it seems everything runs well.
Back to my question - as you mentioned after 150K , they should be changed - should I cahnge the whole thing (hub+gear) or is it enough to change the hub+seals?

Agrector · Post by **Agrector** » 23 Nov 2018, 07:11

I just found this of as the cheapest:
https://www.ipdusa.com/product.asp?s=ez ... ory=basket

https://www.ipdusa.com/product.asp?s=ez ... ory=basket

Post by **chrism** » 23 Nov 2018, 09:05

Canadian Moose wrote: ↑12 Sep 2016, 19:41 Anyway, I decided to just yank the cam covers off the 2 motors and swap the non VVT intake cam from the old motor onto the new motor. My old motor didn't have VVT on the intake cam. Will be less headache in the long run and I won't have to deal with that pulley wearing out again.

If I read this right it sounds like you’re considering converting from VVT to non- VVT. I don’t think you want to do that. Your system (cam timing sensing) is expecting to see the cam timing advance/retard. If that function is removed it seems to me that you will then get cam timing fault codes.

Correct me if I’m wrong.

Agrector · Post by **Agrector** » 23 Nov 2018, 11:20

Nah, no way! I want to keep the VVT!

Canadian Moose · Post by **Canadian Moose** » 16 Feb 2019, 18:04

chrism wrote: ↑23 Nov 2018, 09:05
Canadian Moose wrote: ↑12 Sep 2016, 19:41 Anyway, I decided to just yank the cam covers off the 2 motors and swap the non VVT intake cam from the old motor onto the new motor. My old motor didn't have VVT on the intake cam. Will be less headache in the long run and I won't have to deal with that pulley wearing out again.
If I read this right it sounds like you’re considering converting from VVT to non- VVT. I don’t think you want to do that. Your system (cam timing sensing) is expecting to see the cam timing advance/retard. If that function is removed it seems to me that you will then get cam timing fault codes.

Correct me if I’m wrong.

Old thread but figure I would comment. Next time I am due for cam seals/timing belt I will swap the exhaust cam for NA one with regular pulley and put a block off plate for VVT solenoid. If I leave the solenoid connected I shouldn't get any codes. The ECU won't know any better.

Post by **abscate** » 16 Feb 2019, 19:30

I don't think is right. When the ECU sends the solenoid an advance command, and does not detect advance on the cam sensor, it will code.

Canadian Moose · Post by **Canadian Moose** » 17 Feb 2019, 07:36

abscate wrote: ↑16 Feb 2019, 19:30 I don't think is right. When the ECU sends the solenoid an advance command, and does not detect advance on the cam sensor, it will code.

We shall see. I know people welded their VVT pulleys solid before and didn't get codes.

CVVT hub diagnosis

Re: CVVT hub diagnosis