Sheared off No 1 Manifold stud?

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Re: Sheared off No 1 Manifold stud?

Post by waycar8 » Sun Oct 25, 2009 6:27 pm

hembramacho wrote: The cost of a new gasket might be cheaper than the labour needed to skim the original one anyway.

Andrew

:shock: :shock: , thats a no no Andrew, if its warped get it skimmed or you will be back to square 1, as the warped manifold will put pressure on your new studs and will shear those too eventually, figers crossed it isnt warped and you have caught it in time [-o<

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Re: Sheared off No 1 Manifold stud?

Post by mikeonb4c » Sun Oct 25, 2009 6:37 pm

hembramacho wrote:
mikeonb4c wrote:You'd think not provided the old ones come out without breaking [-o<

Ar those prices for the manifold or just the gasket?
Fair point about them breaking but by replacing the gasket or sort the original one they would all have to come off anyway, broken or not. That price is for the gasket only - as far as I can see the manifold itself is fine. [-o< The studs are £3.50 each too so I suppose it's £50 for new parts before labour. Peace of mind might swing it for me though. The cost of a new gasket might be cheaper than the labour needed to skim the original one anyway.

Andrew
Ah! Becuase they are called studs, I'd assumed they were just lengths of steel, one half threaded one way to screw into the block, the other way the other way to take a nut, and that they stayed in the block while you simply removed the nuts that held the manifold in place. Thats how I recall studs on engines I worked on years back. Are they effectively just hex headed bolts then, that screw into the block to hold the manifold in place? If so I can see what you're saying (but still £3.50 each as you say!).
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Re: Sheared off No 1 Manifold stud?

Post by hembramacho » Sun Oct 25, 2009 7:40 pm

waycar8 wrote:
hembramacho wrote: The cost of a new gasket might be cheaper than the labour needed to skim the original one anyway.

Andrew

:shock: :shock: , thats a no no Andrew, if its warped get it skimmed or you will be back to square 1, as the warped manifold will put pressure on your new studs and will shear those too eventually, figers crossed it isnt warped and you have caught it in time [-o<

Regards Wayne
Thanks Wayne.
I think I've got confused between skimming the gasket and the manifold itself. :oops: Can you tell if the manifold is warped just by looking at it? It looked OK but I realise this doesn't necessarily mean it is OK.
I'm hoping it is just a replacement gasket that I need, and thought I might as well replace all the studs also to be safe. I'm sure the garage will check if the manifold is Ok anyway, although I will mention it too when I drop it off, whenever that will be.

Andrew
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Re: Sheared off No 1 Manifold stud?

Post by dandywarhol » Sun Oct 25, 2009 7:50 pm

mikeonb4c wrote:
hembramacho wrote:
mikeonb4c wrote:You'd think not provided the old ones come out without breaking [-o<

Ar those prices for the manifold or just the gasket?
Fair point about them breaking but by replacing the gasket or sort the original one they would all have to come off anyway, broken or not. That price is for the gasket only - as far as I can see the manifold itself is fine. [-o< The studs are £3.50 each too so I suppose it's £50 for new parts before labour. Peace of mind might swing it for me though. The cost of a new gasket might be cheaper than the labour needed to skim the original one anyway.

Andrew
Ah! Becuase they are called studs, I'd assumed they were just lengths of steel, one half threaded one way to screw into the block, the other way the other way to take a nut, and that they stayed in the block while you simply removed the nuts that held the manifold in place. Thats how I recall studs on engines I worked on years back. Are they effectively just hex headed bolts then, that screw into the block to hold the manifold in place? If so I can see what you're saying (but still £3.50 each as you say!).
They are studs as you describe Mike - permanently in the HEAD (or until they come out!) and the manifold is secured to the studs by metalok nuts
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Re: Sheared off No 1 Manifold stud?

Post by hembramacho » Sun Oct 25, 2009 7:57 pm

dandywarhol wrote: They are studs as you describe Mike - permanently in the HEAD (or until they come out!) and the manifold is secured to the studs by metalok nuts
Does that mean you can replace the gasket without the need for taking all the studs out?

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Re: Sheared off No 1 Manifold stud?

Post by mister munkey » Sun Oct 25, 2009 8:03 pm

If I could live my life again . . . . .

I would absolutely change gasket & have manifold double checked for trueness & skimmed if ness.

Having to go through the whole shananigans twice in a month was just too much!

:evil:

Tread carefully, don't rush it, it costs more in the long run.
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Re: Sheared off No 1 Manifold stud?

Post by hembramacho » Sun Oct 25, 2009 8:11 pm

mister munkey wrote:If I could live my life again . . . . .

I would absolutely change gasket & have manifold double checked for trueness & skimmed if ness.

Having to go through the whole shananigans twice in a month was just too much!

:evil:

Tread carefully, don't rush it, it costs more in the long run.
Thanks for that Mr M.
Will get everything checked. For the cost of a new gasket it's probably worth changing that anyway but having looked at previous threads (including yours) this seems pretty pointless without checking the manifold itself.

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Re: Sheared off No 1 Manifold stud?

Post by dandywarhol » Sun Oct 25, 2009 10:41 pm

hembramacho wrote:
dandywarhol wrote: They are studs as you describe Mike - permanently in the HEAD (or until they come out!) and the manifold is secured to the studs by metalok nuts
Does that mean you can replace the gasket without the need for taking all the studs out?

Andrew
Haven't done it (yet :? ) - but as they're all studs then you don't need to take them out. I've yet to know why it's always no.1 that fails though................... :?
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Re: Sheared off No 1 Manifold stud?

Post by hembramacho » Mon Oct 26, 2009 11:12 am

Ordered a new manifold gasket and 8 new studs this morning.
Also ordered EGR blanking plates to be done at the same time.
Booked the bongo into the garage to have the work done a week on Thursday.
Bongo confined to barracks! :(

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Re: Sheared off No 1 Manifold stud?

Post by Romney_YW » Fri Oct 30, 2009 2:18 am

Just to add a few pennies worth.....

hembramacho's photos clearly show something unusual. Notice the dark staining on the head next to the end of the exhaust manifold, below the oil filler - particularly noticeable in photo 2. There could be a number of causes for this, but it looks suspiciously like leaking exhaust fumes to me. My Bongo showed very similar staining. Along with the squealing noises - in my case most frequent when pulling away from stopped - I'd say definite leaking manifold gasket, and given the Bongo's reputation, likely broken exhaust stud.

Mine had sheared No1 stud (as shown in the photos) and the nut was quite clearly missing when I inspected it. I also had No8 sheared - not so easy to inspect because of the exhaust heat baffle, and also the head had not dropped off! It hadn't sheared right through - so I only found it when I put the spanner on it to remove the whole manifold in order to get the stud extractor on the broken stud at No1, when of course it just twisted off leaving the broken bit flush with the head. :shock: Fortunately I was able (very carefully!) to centre drill this and then it shifted very easily with an 'Easiout' thread extractor. Big sighs of relief, I can assure you.

I was able to get almost identical replacement studs at a local Land Rover spares shop (Land Rover Supermarket - http://www.lrparts.net/) - about £1.50 for 2 if I recall. :)

I put a steel straight-edge across the exhaust manifold and discovered that it was badly warped - possibly several mm from one end to the other. Not surprising the studs had snapped. Luckily for me, my brother has a decent workshop - so we mounted the manifold up and cautiously milled a little bit off it until the straight-edge showed it was flat again. A bit nerve-wracking but fortunately no major cost. I hope that my manifold has done all the warping it is going to, and will now remain flat in the future.

I seem to recall once reading something about leaving rough castings (outside?) for a while to let the stresses and strains dissipate before the machining is carried out. I guess if it isn't left long enough ....... Also an exhaust manifold has a pretty severe life - heating up to quite high temperatures, cooling down again, etc., etc. It's enough to drive any self-respecting casting round the bend ...... :roll:

Oh, and while I had it all in bits, we made up a plug for the back of the manifold and dismantled the EGR valve which was showing signs of leaking fumes at the weld on the flange underneath the EGR valve itself.

The Bongo now shows a tidy turn of speed for a vehicle of its size. :evil:
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Re: Sheared off No 1 Manifold stud?

Post by mikeonb4c » Fri Oct 30, 2009 2:49 pm

Romney_YW wrote:Just to add a few pennies worth.....

hembramacho's photos clearly show something unusual. Notice the dark staining on the head next to the end of the exhaust manifold, below the oil filler - particularly noticeable in photo 2. There could be a number of causes for this, but it looks suspiciously like leaking exhaust fumes to me. My Bongo showed very similar staining. Along with the squealing noises - in my case most frequent when pulling away from stopped - I'd say definite leaking manifold gasket, and given the Bongo's reputation, likely broken exhaust stud.

Mine had sheared No1 stud (as shown in the photos) and the nut was quite clearly missing when I inspected it. I also had No8 sheared - not so easy to inspect because of the exhaust heat baffle, and also the head had not dropped off! It hadn't sheared right through - so I only found it when I put the spanner on it to remove the whole manifold in order to get the stud extractor on the broken stud at No1, when of course it just twisted off leaving the broken bit flush with the head. :shock: Fortunately I was able (very carefully!) to centre drill this and then it shifted very easily with an 'Easiout' thread extractor. Big sighs of relief, I can assure you.

I was able to get almost identical replacement studs at a local Land Rover spares shop (Land Rover Supermarket - http://www.lrparts.net/) - about £1.50 for 2 if I recall. :)

I put a steel straight-edge across the exhaust manifold and discovered that it was badly warped - possibly several mm from one end to the other. Not surprising the studs had snapped. Luckily for me, my brother has a decent workshop - so we mounted the manifold up and cautiously milled a little bit off it until the straight-edge showed it was flat again. A bit nerve-wracking but fortunately no major cost. I hope that my manifold has done all the warping it is going to, and will now remain flat in the future.

I seem to recall once reading something about leaving rough castings (outside?) for a while to let the stresses and strains dissipate before the machining is carried out. I guess if it isn't left long enough ....... Also an exhaust manifold has a pretty severe life - heating up to quite high temperatures, cooling down again, etc., etc. It's enough to drive any self-respecting casting round the bend ...... :roll:

Oh, and while I had it all in bits, we made up a plug for the back of the manifold and dismantled the EGR valve which was showing signs of leaking fumes at the weld on the flange underneath the EGR valve itself.

The Bongo now shows a tidy turn of speed for a vehicle of its size. :evil:
Excellent post - I enjoyed that =D>
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Re: Sheared off No 1 Manifold stud?

Post by hembramacho » Fri Oct 30, 2009 5:51 pm

Romney_YW wrote:Just to add a few pennies worth.....

hembramacho's photos clearly show something unusual. Notice the dark staining on the head next to the end of the exhaust manifold, below the oil filler - particularly noticeable in photo 2. There could be a number of causes for this, but it looks suspiciously like leaking exhaust fumes to me. My Bongo showed very similar staining. Along with the squealing noises - in my case most frequent when pulling away from stopped - I'd say definite leaking manifold gasket, and given the Bongo's reputation, likely broken exhaust stud.

Mine had sheared No1 stud (as shown in the photos) and the nut was quite clearly missing when I inspected it. I also had No8 sheared - not so easy to inspect because of the exhaust heat baffle, and also the head had not dropped off! It hadn't sheared right through - so I only found it when I put the spanner on it to remove the whole manifold in order to get the stud extractor on the broken stud at No1, when of course it just twisted off leaving the broken bit flush with the head. :shock: Fortunately I was able (very carefully!) to centre drill this and then it shifted very easily with an 'Easiout' thread extractor. Big sighs of relief, I can assure you.

I was able to get almost identical replacement studs at a local Land Rover spares shop (Land Rover Supermarket - http://www.lrparts.net/) - about £1.50 for 2 if I recall. :)

I put a steel straight-edge across the exhaust manifold and discovered that it was badly warped - possibly several mm from one end to the other. Not surprising the studs had snapped. Luckily for me, my brother has a decent workshop - so we mounted the manifold up and cautiously milled a little bit off it until the straight-edge showed it was flat again. A bit nerve-wracking but fortunately no major cost. I hope that my manifold has done all the warping it is going to, and will now remain flat in the future.

I seem to recall once reading something about leaving rough castings (outside?) for a while to let the stresses and strains dissipate before the machining is carried out. I guess if it isn't left long enough ....... Also an exhaust manifold has a pretty severe life - heating up to quite high temperatures, cooling down again, etc., etc. It's enough to drive any self-respecting casting round the bend ...... :roll:

Oh, and while I had it all in bits, we made up a plug for the back of the manifold and dismantled the EGR valve which was showing signs of leaking fumes at the weld on the flange underneath the EGR valve itself.

The Bongo now shows a tidy turn of speed for a vehicle of its size. :evil:
Thanks for that.
Regards to the stain, there is definitely a leak as when water/fairy liquid was sprayed on the area there was a bit of bubbling which indicates a leak of some sort I would guess.
I'm hoping that with a new manifold gasket, as well as all new studs, my problem will be sorted. Also blanking off the EGR will help, although my blanking plates haven't arrived yet - I hope they haven't been lost in all the strike chaos. Thinking back I've also noticed a drop in MPG so that could explain that one too. [-o< I'm also wondering if my starting up juddering issue could be caused by this also, although this seems to have been cured by fitting a non-return valve on the fuel filter. What would be nice is that after the bongo goes in to get this work done it runs like a dream! [-o< [-o< [-o<

Andrew
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Re: Sheared off No 1 Manifold stud?

Post by Doone » Fri Oct 30, 2009 6:18 pm

Andrew you have a pm. :)
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Re: Sheared off No 1 Manifold stud?

Post by Romney_YW » Sat Oct 31, 2009 12:20 pm

mikeonb4c - thanks for the praise. I try my best, but I'm still very much a Bongo beginner! :)

hembramacho - good luck with the fix. My Bongo's oodles better as a result of the repairs. Hope yours will be too.

Best wishes, Romney
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Re: Sheared off No 1 Manifold stud?

Post by mikeonb4c » Sat Oct 31, 2009 1:53 pm

Romney_YW wrote:mikeonb4c - thanks for the praise. I try my best, but I'm still very much a Bongo beginner! :)
No worries. You may be new to Bongos, but you appear to be no stranger to common sense and resourcefullness 8)
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