Head bolts - what now?

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Originally Posted by discorevy

Back off the ones you angled wrong first, one by one by 180 degress in reverse sequence ,then back them all off by 90 , getting back to stage 2 on all of them , then replace with the new bolts, one by one in sequence back up to stage 2 , omitting stage 1 , this will keep even tension on the head also keeping the gasket crushed, don't forget to mark the bolt flanges before the last stages.

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Sorry for butting in Discorevy.
Nick

This may be a bit late to help you now but here's an alternate method of tightening the head bolts.

Step 1. Throw the angle gauge into bin where it belongs. These things are truly the spawn of the devil :firedevil:

Step 2. Tighten head bolts to second stage ie 65 Nm

Step 3. Mark cylinder head and bolt head as shown using an indelible marker.

Attachment 139807

Step 4. Tighten head bolt a further 90 degrees, the correlation between the marks should now look like this.

Attachment 139808

Step 5. Tighten the head bolt a further 180 degrees, the correlation between the marks should now look like this.

Attachment 139809

Step 6. After adding the last 45 degrees it should now look something like this.

Attachment 139810


The idea is to use the 'pattern' of the bolt heads 60 degree segments to torque the head down correctly.

There are several benefit of doing it this way.

1/. You don't lose count of which bolt you're up to as you have a visual reference of the state of torque on each bolt.

2/. No external angle gauge required which can be a PITA to use and keep correctly calibrated.

3/. Very easy to pick up where you left off if distracted/called away/unable to complete in one hit.

Deano :)

Just put ARP studs in - a lot better, safer and easier to do - and reusable.

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Originally Posted by garrycol

Just put ARP studs in - a lot better, safer and easier to do - and reusable.

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It's not a v8 , even if ARP did make studs for a td5 ( which they don't), you would have to pull the engine to remove the head or remove the studs, defeating part of the benefit.

Quote:

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Originally Posted by Pippin

Sorry for butting in Discorevy.
Nick

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You weren't butting in Nick , especially when you have relevant info, just in this case it's important to keep even torque over the head and also to keep crush on the gasket

Quote:

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Originally Posted by discorevy

It's not a v8

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Oh Ok - would have been helpful to have been given that information in the first post - does help answer the question. I wonder how many answers were based on the thought it was a V8.

If replacing bolts on a TD5 without removing the head then if ARP studs were available then you could do the same.

garry

Quote:

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Originally Posted by garrycol

Oh Ok - you might have given that information in your first post - does help answer the question. I wonder how many answers were based on the thought it was a V8.

If you are replacing bolts on a TD5 without removing the head then if ARP studs were available then you could do the same.

garry

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No Garry. You couldn’t... because you wouldn’t be able to lift the head off whilst the engine was in situ.

The bolts are about a foot long!

Thanks - I know nothing of the TD5 - if I had known it was a TD5 I would not have commented.

Cheers

Garry

Quote:

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Originally Posted by discorevy

It's not a v8 , even if ARP did make studs for a td5 ( which they don't), you would have to pull the engine to remove the head or remove the studs, defeating part of the benefit.

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ARP don't make studs for TD5. There is a company in the UK that will however, T&K precision - they used to make them to order for a middle man (don't know who) who sold them on to a now shut down business, Chesterfield Race Diagnostics.

I had a set made up, they are stupid money and probably complete overkill in spec ( ~800 quid inc VAT! ), but a fool and his money are easily separated or I wouldn't own a landrover.

Anyhow, you CAN fit these without pulling the engine - undo the bottom gearbox mount bolts and jack up the gearbox to tilt the engine forward, rubber mallet on the scuttle panel creates some extra wiggle space after lifting off the weather strip - no damage incurred.

Some photos (copied this from my D2BC vehicle thread):

Gave the deck a clean
https://www.aulro.com/afvb/images/im...2018/05/20.jpg


Started to fit the studs but got rained off - undoing the gearbox mounts and jacking the gearbox up rotated the block enough so that the head could lift on over the studs
https://www.aulro.com/afvb/images/im...2018/05/21.jpg


Slight hickup whilst fitting the exhaust manifold, one of the studs sheared - luckily it rotated out when tapped with a punch
https://www.aulro.com/afvb/images/im...2018/05/22.jpg


Got all the studs wound in - I cut a slit in an old head bolt and used that as a thread chaser
https://www.aulro.com/afvb/images/im...2018/05/23.jpg


Head lifted on with help of an engine crane borrowed from a mate (Cheers Chris!) - much easier to locate the head with the studs.
https://www.aulro.com/afvb/images/im...2018/05/24.jpg


Nuts torqued down to 70lb ft in 3 stages 30, 50, 70 - used ARP Ultra Torque lube.
https://www.aulro.com/afvb/images/im...2018/05/25.jpg

Due to the large size of the nuts on the studs, the oil shield on the rocker cover needs some minor mods - between the bits that wrap under the injectors are some ears that need bending outward to accommodate the bolts. Without doing this the rocker cover won't sit correctly.

PS, the studs are not keyed so it would be VERY difficult to fit these with the head in situ.

PPS, jacking the gearbox may be less successful for folk that have the acoustic cover in place - mine doesn't.