2005 XC70 Timing belt - timing marks?

[iamhives]

I'm doing a timing belt/idler/tensioner/belt/water pump replacement on a 2005 XC70 2.5T. I've done this job on my other son's V70 so am familiar with the overall procedure but have questions as I get into the same job on this car. I know there are loads of threads about timing belt replacements and timing marks which I've researched but have some specific questions:

1) I'm no expert of VVT but I believe my car has VVT on inlet and exhaust camshafts (is this true for all 2.5t's?). Anyway, when I try to align my camshaft gears when I have my inlet (front?) gear timing mark aligned with the groove on the timing cover, the exhaust timing mark is about 2 teeth off (to the rear) is this OK and caused by the VVT? The car is running perfectly (except for a leaking water pump) so the timing appears to be correct currently. Is it OK for me to proceed marking the gears and belt etc. so that I replace the belt with the cam gears aligned as they are, despite the fact that they do not exactly align with the timing belt cover notches?

2) I understand that there are supposed to be two small marks on the crankshaft gear that should be aligned with a boss on the engine when the engine is in the correct position. I have rotated the engine clockwise multiple times and cannot see the marks on the crankshaft gear. I've even had the younger eyes of my 21 year old son take a look as I rotate the crankshaft manually but there do not seem to be any alignment marks on the crankshaft gear (at least that we can see). As I understand it there are two positions where the camshaft timing marks align but only one where all three (camshafts and crankshaft marks) align. And its important to pick the right one so seems that in the absence of seeing the marks on the crankshaft gear there is a 50/50 chance of being right. What is the reason for one vs the other of these positions being the desired one?. Will it be OK if I gamble and I pick the wrong crankshaft position with the camshafts correctly aligned, as long as I ensure all gears are positioned as they are? If not, in absence of being able to see the crankshaft alignment marks on the gear, is there another way to ensure that I pick the correct one of the 2 positions where the camshaft marks align (notwithstanding the fact from #1 that the camshaft marks are not aligned to the cover anyway). I've seen mention of removing cylinder one sparks plug and coil to find the correct position (TDC, exhaust vs compression?) and if this is correct what is the procedure to use this method to find the correct position?

Trying to use this job to bond a little with my son and teach him a little about car maintenance (vs IT and tech) but currently stymied by these questions.

Thanks for reading this long post!

[jonesg]

I'm doing a timing belt/idler/tensioner/belt/water pump replacement on a 2005 XC70 2.5T. I've done this job on my other son's V70 so am familiar with the overall procedure but have questions as I get into the same job on this car. I know there are loads of threads about timing belt replacements and timing marks which I've researched but have some specific questions:

1) I'm no expert of VVT but I believe my car has VVT on inlet and exhaust camshafts (is this true for all 2.5t's?). Anyway, when I try to align my camshaft gears when I have my inlet (front?) gear timing mark aligned with the groove on the timing cover, the exhaust timing mark is about 2 teeth off (to the rear) is this OK and caused by the VVT? The car is running perfectly (except for a leaking water pump) so the timing appears to be correct currently. Is it OK for me to proceed marking the gears and belt etc. so that I replace the belt with the cam gears aligned as they are, despite the fact that they do not exactly align with the timing belt cover notches?

2) I understand that there are supposed to be two small marks on the crankshaft gear that should be aligned with a boss on the engine when the engine is in the correct position. I have rotated the engine clockwise multiple times and cannot see the marks on the crankshaft gear. I've even had the younger eyes of my 21 year old son take a look as I rotate the crankshaft manually but there do not seem to be any alignment marks on the crankshaft gear (at least that we can see). As I understand it there are two positions where the camshaft timing marks align but only one where all three (camshafts and crankshaft marks) align. And its important to pick the right one so seems that in the absence of seeing the marks on the crankshaft gear there is a 50/50 chance of being right. What is the reason for one vs the other of these positions being the desired one?. Will it be OK if I gamble and I pick the wrong crankshaft position with the camshafts correctly aligned, as long as I ensure all gears are positioned as they are? If not, in absence of being able to see the crankshaft alignment marks on the gear, is there another way to ensure that I pick the correct one of the 2 positions where the camshaft marks align (notwithstanding the fact from #1 that the camshaft marks are not aligned to the cover anyway). I've seen mention of removing cylinder one sparks plug and coil to find the correct position (TDC, exhaust vs compression?) and if this is correct what is the procedure to use this method to find the correct position?

Trying to use this job to bond a little with my son and teach him a little about car maintenance (vs IT and tech) but currently stymied by these questions.

Thanks for reading this long post!

see the photo, theres a molded line, a boss, that sits between the 2 marks on the crank gear.
Line that boss up with the boss on the oil pump and you will see the 2 timing marks.
This assumes you have a good critical light, they are only ticks that are stamped in the face of the gear, you can only see the end of the marks, they aren't stamped on the face that you can see.

[jonesg]

try to find a better picture...

here.
https://www.ebay.com/itm/235609622102?c ... s3EALw_wcB

[lrock]

Thanks for reading this long post!

check this photo
something like this might be helpful

if you buy from amazon don't forget to use the MVS link!

[chrism]

Questions in response to your questions……

Is the old belt still in place?

Are you saying that you can’t get both cam sprockets timing marks to align with the marks on plastic cover at the same time?

Are you getting a check engine light?

[abscate]

You have to find those marks. They are there. It is critical to get the right crank position

The VVT cars need to be turned past the marks and then rotated backwards to bring the marks into alignment. That’s because the cam gears rotate on the cams independently for the VVT function.

[iamhives]

Thanks for the quick and helpful replies! Much appreciated since I'd like to work on this tomorrow! Made some progess:

To Chrism's question: The old belt is in place. The car runs well and has for several years. No check engine light (except when one of the coils went bad!). And yes, I can't get both of the cam sprocket timing marks to align to the marks on the plastic cover at the same time. However, see below since the other responses have helped me identify the marks on the crank gear teeth which changes my questions.

In response to Jonesg and Orocks' posts and the links provided which were VERY helpful. Knowing to look for the boss on the crank pulley side of the crankshaft gear was very helpful and aligning the pin on the crank pulley at the roughly the 1pm position got into the ballpark position - and now I can see the tiny grooves on the back/edge of the crank gear teeth. YAY!

My only remaining problem is: when aligning the newly discovered crank gear groves with the mark on the engine, what I thought were the marks on the cam gears are not even close to aligning with the grooves in the timing belt plastic cover! And as I type this I see Abscate's response about having to turn back to get them into alignment for VVT cars. Can you be more specific. Do I turn CW past the crank mark and then back? If so, by how much. Right now the intake cam mark is about 60 degrees past the alignment and the exhaust cam somewhat less

[lrock]

My only remaining problem is: when aligning the newly discovered crank gear groves with the mark on the engine, what I thought were the marks on the cam gears are not even close to aligning with the grooves in the timing belt plastic cover! And as I type this I see Abscate's response about having to turn back to get them into alignment for VVT cars. Can you be more specific. Do I turn CW past the crank mark and then back? If so, by how much. Right now the intake cam mark is about 60 degrees past the alignment and the exhaust cam somewhat less

is the car a B5254T2 engine? i don't know if you have this or not, but maybe it will help, please note there are two different tensioning procedures depending on the serial number of the engine.

[cn90]

Everything you need is in this thread that I wrote back in 2022...

viewtopic.php?t=100439

[erikv11]

The cam tools are a must IMO.

cn90's thread collects details from all over the internet into one place and should be looked at.

When I was figuring it out I really appreciated this thread, the linked video and the posts by VTL are especially good in summarizing it all in relatively few words: viewtopic.php?t=101950