diesel inlet manifold

[frank rabbets]

Hi All

I'm tempted to take my inlet manifold off to clear all the rubbish out. Is it much of a job [marks out of ten]. Are their waterways involved? If so I might chicken out as it's not an essential job ........ yet.

Frank

 

[karl webster]

Are you running 12 valve frank or 24? if 12valve easy mate 1/10.

karl

 

[Dave Docwra]

Only done the 12 valve, easy job to do not really on the scale at all, the gasket between the turbo section & the manifold should be replaced on re-assembly.

 

[frank rabbets]

It's 24 valve and looks like the injector pipes will have to come off.

Frank

 

[Nick Shepherd]

Is it a job worth doing? What are the positives?

 

[Cptsideways]

It will be clean as a whistle - dont bother!!

There is no EGR to clog it up, maybe some residue from turbo oil, I've taken a few off & they've never needed cleaning out.

 

[frank rabbets]

I took my top tube off to do the tappets and found it full of black oily carbon. There are 2 egr valves. Engine performs OK so I don't think there is a problem. I just assumed that the inlet manifold would be the same. Perhaps not if it's hotter??

Frank

 

[Brett]

It will be clean as a whistle - dont bother!!

There is no EGR to clog it up, maybe some residue from turbo oil, I've taken a few off & they've never needed cleaning out.

Don't think so

If it's anything like mine it'll be filthy & there are 2 EGR valves. on the 24Valve unless it's an import, Aussie models had no EGR, not sure which other markets didn't get them.

 

[Brett]

Hi All

I'm tempted to take my inlet manifold off to clear all the rubbish out. Is it much of a job [marks out of ten]. Are their waterways involved? If so I might chicken out as it's not an essential job ........ yet.

Frank

Frank,

I posted these on the other site a while back, may as well repost here

I had a busy day Saturday, I'd ordered up the following Genuine parts required to do the valve clearances:-

* Rocker Cover Gasket
* Seal Washers (The ones Toyota supplied were not suitable, had to re-use existing)
* RTV Sealant
* EGR to Exhaust Manifold Gasket
* Intake to Inlet Manifold Gasket

I also wanted to change the alternator drive belts as I recently had to replace the aircon belt as the old one snapped. I presumed the alternator belts were possibly due to be changed. Again I used Genuine Toyota parts.

A few tips for anyone else who is considering doing these jobs, first it's a lot easier if you remove the guard just above the steering damper, I also dropped the nearside end of the damper c/w the triangular mounting bracket. This makes rotating the engine on the crank a lot easier & also gives better access for removal/fitting of belts.

I also found that to actually make it possible to see to line up the timing marks on the crank pully & timing cover & to lever the alternator over, it was necessary to remove the aircon compressor. I just removed the four mounting bolts & swung the compressor out of the way. I tied it back to the bonnet strut with tie-wraps.

When I had removed the air intake pipe c/w EGR valves I was absolutley shocked to see how much soot had built up inside I would say about 1" thick all the way around. the internal diameter of the intake must have been reduced by about 50% at least!

To remove all this muck I scraped most out with a small paint scraper/putty knife, then washed the inlet out with solvent, I used a babys bottle brush to clean right around all the little knooks & crannys I'm not sure if it would hurt, but I avoided getting solvent down to the heater assembly.

I don't think the valve cover had ever been off my engine, a clue was the type of sealant used in three positions between the block & valve cover. Toyota use a type of instant gasket they refer to as "Instant Grey" it's part number is referenced in the manual if any purists wish to use it but at £55:00 a tube I would say most garages or home mechanics opt for normal RTV sealant!

If I am correct that the valve cover had never been off my engine, the valve clearances were not far out considering. They had all opened out a bit but not a great deal.

An added bonus of doing the job, I recently posted that my engine had started making the renowned "H series Tick" after it's recent oil & filter change. This has completely gone since setting the clearances correctly.

All in all it's not a bad job, looks a bit daunting with all the vacuum pipes & intake etc. But it's made a lot of difference to my truck, it's got to be worth it just to clean all that crud out of the intake!

Oh, yeah, my old alternator belts were perfect They'll make good spares!

 

[Cptsideways]

Aha if it has EGR then it will clogged up & worth a clean

 

[frank rabbets]

Thanks Brett

Did you clean out your inlet manifold or was it not too bad? Is it easy to see into the manifold with it still on the engine? I don't fancy taking off the manifold only to find it's clean. Its done 128000 miles. Did your cleaning improve your fuel consumption?

Thanks again
Frank

 

[Brett]

Frank,
as mentioned in my previous post.

When I had removed the air intake pipe c/w EGR valves I was absolutley shocked to see how much soot had built up inside I would say about 1" thick all the way around. the internal diameter of the intake must have been reduced by about 50% at least!

To remove all this muck I scraped most out with a small paint scraper/putty knife, then washed the inlet out with solvent, I used a babys bottle brush to clean right around all the little knooks & crannys I'm not sure if it would hurt, but I avoided getting solvent down to the heater assembly.

All in all it's not a bad job, looks a bit daunting with all the vacuum pipes & intake etc. But it's made a lot of difference to my truck, it's got to be worth it just to clean all that crud out of the intake!

I didn't notice any improvement in consumption, mine is good anyway, I average over 30mpg all the while.

 

[LandCruiser1978]

To revive an old thread

I've done this today ..

24v upper manifold pipe .. (from egr / turbo to the inlet manifold)

I stripped this down today .
Found that the pipe was FULL ov crud , real oily carbony mess . scraped it out then washed it out with hot water fairy liquid and elbow grease ..
Nice and clean now .. I also made a blanking plate for the egr . so now no more crud

The heater element was nice and clean albeit slightly oiley ..

Now my question is the actual manifold is also full of crud but i can't clean it off as it's still attached to the block .
Now i didn't want to disturb any of the crud becuase i didn't want it falling into the engine .. is there anything i can do other than taking the manifold completely off?
And also would it make a difference .

I have noticed since putting it back together the engine seems quieter . but that could be becuase one of my EGR's were leaking becasue one of the bolts had fallen out

 

[Towpack]

The only way to properly clean the intake manifold is to remove it. You will be able to carefully srape out the crud from just inside the inlet to the manifold but you won't be able to get to all the individual ports so if you can't do it right why bother? It will almost certainly improve the gasflow into the engine and let it breath more easily which should improve engine efficiency but, IMO, measurable gains will be small. At least with the EGR's disabled the build up won't get any worse.

 

[LandCruiser1978]

if you can't do it right why bother? It will almost certainly improve the gasflow into the engine and let it breath more easily which should improve engine efficiency but, IMO, measurable gains will be small. At least with the EGR's disabled the build up won't get any worse.

I think i'll leave the manifold
maybe now the egr is blocked it might slowly clean it's self .
There's wishful thinking

 

[fridayman]

viewtopic.php?f=47&t=13511

 

[Towpack]

http://www.landcruiserclub.net/forum/viewtopic.php?f=47&t=13511

After seeing the crud that builds up in the intake side I just can't see how a can of anything will clean it out, and even if it did, I certainly wouldn't want it being flushed through the engine. The air supply on the diesels isn't throttled so there is no throttle body to clean, only the pipework that makes up the intake tract. The throttle works solely on the pump fuelling.

 

[frank rabbets]

I cleaned out my inlet manifold when attached to the block with a hoover nozzle and scraper to prevent bits being left in the manifold and then being sucked into the engine. I only managed to get to a small section though. I was temted to remove the manifold but didn't because then I would have been temted to take the 'head off !

Frank

 

[fridayman]

http://www.landcruiserclub.net/forum/viewtopic.php?f=47&t=13511

After seeing the crud that builds up in the intake side I just can't see how a can of anything will clean it out, and even if it did, I certainly wouldn't want it being flushed through the engine. The air supply on the diesels isn't throttled so there is no throttle body to clean, only the pipework that makes up the intake tract. The throttle works solely on the pump fuelling.

I don't think it does an amazing job, but it seems to have made a difference on my 90. On the 90's there is a throttle body which can get a bit gummed up.

 

[LandCruiser1978]

If the inlet looks like sh1t imagine what the top of the valves must look like ..