Disco 4SE, blown air intake manifold.

[dave12]

A loud bang & lots of smoke. Limited power message pops up & limped home. Confirmed RH air inlet manifold split. Couldn't believe it was made of plastic. After many $$ later it was repaired satisfactorily with additional bits replaced. IE pulleys, hoses, gaskets etc. My concern is how long before the LH manifold goes? My landy has done 120K.

[justinc]

I wouldve done both...and the lh one is easier to replace. The only time i would do only 1 of them is after advice from the customer re costs.

Jc

[Quicky]

I have had the left (facing the front of the vehicle) replaced. Discussed with the wife about replacing the right one at the same time as a known issue with the wife (accountant), no is not a long discussion. Now the other side has gone and due to the Christmas break, I was unable to have it repaired until the 03/01/19. So rather than gimp around I decided to repair the crack with some epoxy as I have quite a bit of experience with fibre glassing boats, etc.So for those those that are interested, these are the steps I took:

Remove (rip, cut) foam rubber insulation from the around the injectors;
Using a spray bottle of soapy water, determine the extent of the crack with the engine running;
Thoroughly clean all surfaces with kerosene;
Clean surfaces around the crack;
Remove anti-vibration clip and rubber from injector delivery pipes;
Loosen any injector pipes at both the injector and rail delivery that inhibit access, you may have to as I did and completely remove from the injector end to be able to swing the pipe out of the way, ensure you cover any open injectors to prevent foreign material entering;
Thoroughly key all surfaces around the crack, I used my Dremel as it has a long shaft and with the carbide bit i could get into tight angles and the rotary sander drum for flat easy access areas;
Thoroughly clean with acetone;
Cut some woven cloth to size;
Mix the epoxy, I used G-flex Epoxy Adhesives | Specialty Epoxies - WEST SYSTEM by ATL Composites (http://www.westsystem.com.au/west_system/products/specialty_epoxies) as I have repaired poly tanks with this product;
I also thickened the product with 403 Microfibres Fillers - WEST SYSTEM by ATL Composites (http://www.westsystem.com.au/west_system/products/fillers);
Apply epoxy to the surfaces using a suitable applicator. I used cotton buds, but a stiffish artist brush would also be suitable;
Place precut cloth onto wetted surface and stipple the epoxy mix ove the area ensuring a thorough wetting;
Once complete, continue checking for epoxy running over the edge of the manifold (manifold has a handy lip to help prevent this) as you won't want to have the manifold permanently attached;
Reinstall all fuel fittings;
Start engine and retest with soapy water, if you have done a good job its goodbye gimp!

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[Graeme]

Unfortunately idling does not stress test the repair as the cracks occur due to flexing of the plastic under high boost. Hopefully the repair will buy some time.

[DiscoJeffster]

Others have tried and failed at this but as Graeme says, will probably buy you a month.

[Graeme]

Keep an eye on those loosened injector pipes as they're meant to be single use so may leak, although not having removed the injectors, the fittings should line-up exactly as they did originally. If an injector is removed or even just loosened then the pipe vs injector angle is likely to have changed thereby increasing the leak risk.

[justinc]

Keep an eye on those loosened injector pipes as they're meant to be single use so may leak, although not having removed the injectors, the fittings should line-up exactly as they did originally. If an injector is removed or even just loosened then the pipe vs injector angle is likely to have changed thereby increasing the leak risk.

100% correct Graeme, I have had these vehicles present with leaks from rail to HPFP pipe leaks after a HPFP replacement, I'm certain there have been fires caused by this issue in the past....

[DiscoJeffster]

100% correct Graeme, I have had these vehicles present with leaks from rail to HPFP pipe leaks after a HPFP replacement, I'm certain there have been fires caused by this issue in the past....

And of interest, right or wrong, service agent Disco Mikey in the UK, regularly posting to Disco UK has never replaced the hose pipes when replacing any intake manifolds according to him. Now I’ve researched the impact of reusing the pipes and the claim from the manufacturer is that it’s not that they leak but that re-tightening the pipe further compresses the opening and causes restriction to flow. They show a cross section of a retightened pipe, admittedly I take a pinch of marketing salt and assume they tightened it to 200nm to get the photographed effect lol.

[justinc]

And of interest, right or wrong, service agent Disco Mikey in the UK, regularly posting to Disco UK has never replaced the hose pipes when replacing any intake manifolds according to him. Now I’ve researched the impact of reusing the pipes and the claim from the manufacturer is that it’s not that they leak but that re-tightening the pipe further compresses the opening and causes restriction to flow. They show a cross section of a retightened pipe, admittedly I take a pinch of marketing salt and assume they tightened it to 200nm to get the photographed effect lol.

There is very little flow anyway, it's all about pressure so I doubt that claim from the manufacturer.... highly atomized diesel mist in a hot engine compartment is far more dangerous!😯

[DiscoJeffster]

There is very little flow anyway, it's all about pressure so I doubt that claim from the manufacturer.... highly atomized diesel mist in a hot engine compartment is far more dangerous![emoji54]

As always when a supplier of something tells me something that lines their pocket I ask questions. Case and point below. This is the article I was referring to.

Injector Tech Tips - Re-use Of High Pressure Injector Pipes | Delphi Auto Parts (https://www.delphiautoparts.com/fra/en/toolbox/injector-tech-tips-re-use-high-pressure-injector-pipes)

I don’t necessarily buy into it but none the less, food for thought and up for debate.

[Quicky]

New manifold installed. Attached is a photo of repaired article, a bit rough due to access, but still serviceable after 2,625 km.
147833

[Eric SDV6SE]

The crack seems to propagate from the circular hole - is there anything held in those holes or bolted through?

That hole seems like a bit of a stress raiser, especially if that area is fixed, and the rest of the manifold surface flexes due to intake air pressure and engine temperature.

I've just had a look at my manifolds and mine seem to be a different design.

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