Lift Bolt Paranoia

[Big_Sid]

It's only been a few months since I'd even heard about lift bolts and their presence in the VVTL-i engines, but since then, i'm now starting to wonder if my lift is lacking the kick it once had and therefore wondering if my bolts are badly worn or broken.

I don't want to go taking my engine to bits to check them if I'm just being paranoid (and also because it'll mean having to buy a socket set), but on the other hand, I don't want them to snap off as I've heard this can be very costly to get put right.

On the subject of them snapping, from pictures I've seen, they all seem to stay in the rocker shaft rather than fall into the engine as some have suggested, so I guess my question is this...

Should I give in to my paranoia and check them, or should I wait until I feel a definite lack of lift before I start messing around with the engine?

If I wait until my lift has certainly gone (rather than me just imagining it feels weaker), what are the odds of having part of the sheared bolt end up in some nasty place in the engine?

Also, off topic, but does anyone have a link to a guide on de-butterflying the gen 7? I've searched about but can't find anything really.

Thanks - Sid

[aquazi]

It's only been a few months since I'd even heard about lift bolts and their presence in the VVTL-i engines, but since then, i'm now starting to wonder if my lift is lacking the kick it once had and therefore wondering if my bolts are badly worn or broken.

I don't want to go taking my engine to bits to check them if I'm just being paranoid (and also because it'll mean having to buy a socket set), but on the other hand, I don't want them to snap off as I've heard this can be very costly to get put right.

On the subject of them snapping, from pictures I've seen, they all seem to stay in the rocker shaft rather than fall into the engine as some have suggested, so I guess my question is this...

Should I give in to my paranoia and check them, or should I wait until I feel a definite lack of lift before I start messing around with the engine?

If I wait until my lift has certainly gone (rather than me just imagining it feels weaker), what are the odds of having part of the sheared bolt end up in some nasty place in the engine?

Also, off topic, but does anyone have a link to a guide on de-butterflying the gen 7? I've searched about but can't find anything really.

Thanks - Sid

What age is your car?

The facelift ones, thats post 03 have revised lift bolts, which are less prone to breaking - never heard of facelift bolts breaking.

If the bolts are broken you are in for an expensive replacement as like you said they are usually sheared in the rocker shaft, so are close to impossible to remove.

So if you have a pre facelift i would changed the bolts. They cost about £2 each so £8 for the set, and can be changed in 30 mins with a 10mm socket.

I think if they bolts are broken you literally dont have lift, and not a lack of lift. The real test, let the engine heat (as it wont lift when cold) up and then drive it to 6k prm and see if it happens!

Debutterflying is very simple... open the air box, 3 clips i think.... you dont have to remove the rear hose but it makes it easier... remove your panel filter. on the bottom of the airbox in the center you will see black thing that has a white flap in the middle (this is the butterfly valve) remove the little hose connected to this and then grab it and pull it upwards... its held by two little black clips on the bottom... one of my clips broke when i removed mine.

Make sure you seal up the hose that was connected to it otherwise crap may get into your engine... i used a tyre value cap and some tape.. other have put screws into theirs.

Noticed you are in the midlands, if you live near derby i can give you hand one weekend to do them, lift bolts and butterfly valve are very simple to do - as long as the bolts not already broken!

[Big_Sid]

What age is your car?

The facelift ones, thats post 03 have revised lift bolts, which are less prone to breaking - never heard of facelift bolts breaking.

If the bolts are broken you are in for an expensive replacement as like you said they are usually sheared in the rocker shaft, so are close to impossible to remove.

So if you have a pre facelift i would changed the bolts. They cost about £2 each so £8 for the set, and can be changed in 30 mins with a 10mm socket.

I think if they bolts are broken you literally dont have lift, and not a lack of lift. The real test, let the engine heat (as it wont lift when cold) up and then drive it to 6k prm and see if it happens!

Debutterflying is very simple... open the air box, 3 clips i think.... you dont have to remove the rear hose but it makes it easier... remove your panel filter. on the bottom of the airbox in the center you will see black thing that has a white flap in the middle (this is the butterfly valve) remove the little hose connected to this and then grab it and pull it upwards... its held by two little black clips on the bottom... one of my clips broke when i removed mine.

Make sure you seal up the hose that was connected to it otherwise crap may get into your engine... i used a tyre value cap and some tape.. other have put screws into theirs.

Noticed you are in the midlands, if you live near derby i can give you hand one weekend to do them, lift bolts and butterfly valve are very simple to do - as long as the bolts not already broken!

Thanks for the reply. My Gen 7 is a pre-facelift 2001 with nearly 75k miles on the clock. On the way to work this morning, once the engine had warmed, I pulled out onto a dual carriageway and booted it... I did feel the lift, so I'm guessing they're not broken as you said I'd get no lift at all. Maybe its just me being paranoid and or getting used to the kick it gives.

I've seen some articles on removing broken lift bolts, and it looks fairly straighforward... needing a sharp metal drill bit and a reverse thread set, a steady hand and being careful not to damage the threaded hole on the rocker shaft if they are indeed broken.

I was mainly worried about the sheared bolt dropping further down into the engine somehow, although I think this is an impossibility due to the design of the cam housing, but I suppose theoretically it would be possible for the piece to jam between a cam lobe and a rocker arm if it dropped out of the bottom of the rocker shaft which I'm guessing would end up smashing the engine to bits in the process (and that WOULD be pricey to repair).

By the way, thanks for the offer aqauzi, I live near Coventry, so I might take you up on that one day :D

Thanks - Sid