dmax valve adjustment , rocker cover gaskets
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Author:  Danno [ Tue Nov 13, 2018 3:29 pm ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

4jj1 wrote:
thanks danno yeah i know the provent has an over presure valve built into the lid an another type of valve at the outlet. my injector seals and crankcase gasket started leaking a little oil vapour around the time i installed my genuine provent , after 20k its got steadily worse and started blowing off the pressure valve around the provent lid. until i recently removed it. any filter no matter how good is going to more restrictive than the 20 cm long factory pipe straight into the turbo, thus at least slightly increasing crankcase pressure.
not sure at this stage what my next move is

The injector seals are known to weep regardless after the first time the valves are done as they stopped replacing them automatically after a service a while back due to the expense.
Have you got excessive blow by on that motor? my Provent filter lasted 80k on the Dmax without being cleaned and then 3k on my current car before I replaced it without ever blowing the valve, also a Provent can take up to 3000k or even more before they actually start to work properly and leak into the tube so if yours started straight away I'd be wondering why and perhaps look at the oil your using for a start? The benefits of having these things fitted is beyond doubt so it would be in your interest to have it on there, especially if you haven't got your EGR blocked.

Author:  4jj1 [ Thu Nov 15, 2018 12:52 pm ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

ive used delo 400 for the last 40k, i have always replaced oil and all filters every 10k since new. i used oil resistant hose with the provent set up. it is 16mm i.d. same as factory pipe and rocker outlet. no kinks 90mm elbows.

like danno said i doubt the nice people that did the major service at 80k changed the seals or did the valves. i changed the injector seals and the rocker gasket last week when i did the valves. but it had stopped leaking for the fortnight before i changed them once id removed the provent?????? i gernied the cover when i took the vent off.

anyhow moving forward , do you guys think i should just put the provent back on and see how it goes with the new seals? ive heard you can clean the filters with turps or petrol? if i put it back on ill try and post a picture of the set up, the provent was mounted on the firewall next to the factory fuel filter.

thank you both for your help, ive got more questions but maybe ill save them for another thread, instead of getting side tracked.

Author:  mydmax [ Thu Nov 15, 2018 1:57 pm ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

It is good to have the oil mist contained and not enter the intake stream, so having the Provent should work properly. Possibly best to look inside and see if all the valving is free to operate as intended. I presume you have the flow of gas passing through it is going the correct direction. I can't see how it was building up pressure.

Not sure if you have an EGR restrictor plate. They do lessen the flow of EGR hot exhaust gas into the intake. Too much restriction and it will throw a code and enter limp mode. Do you have a code reader to see codes and reset the code so all is ok again?
Both the catch can and the restrictor plate lessen intake buildup.

Those nice people you mentioned, is there evidence the cover had been off before you doing it? Often they aren't done at 40,000, despite what the logbook states, and so the next ones determine/presume it was done at the 40,000 and deem it unnecessary to do again at 80,000km. That then means, from new they haven't been done at all after 80,000km. I know of some Toyota 80 series vehicles have been detected as not ever having been done or checked even after 200,000km, because everyone before then presumed it was done previously so they don't need to and the next one will. Great logbook service it is.

Author:  Danno [ Thu Nov 15, 2018 8:04 pm ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

I'd just put it back on but I would seriously advise against trying to clean the filter, I did that and although I succeeded in the end it was a waste of time and is likely to damage the filter itself, mainly the shiny paper/fabric that the filter is wrapped in which is made that way for a reason as it turned out and it roughens up during cleaning and doesn't work as well. If it's got less than 30k on it it will be alright. If you must clean it use petrol and don't squeeze it at all to remove the excess petrol, it will need a surprising amount of fuel to clean it too. It will then spend about 3000k's clogging back up so it works again...

MD, they always remove the rocker cover and seal it back down whether they do the valves or not, it's really obvious if they don't so if you don't actually stand there and watch you'll never know..

Author:  4jj1 [ Fri Nov 16, 2018 8:03 am ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

thanks danno, i was just trying to clean the filter when i gave up and came inside and read your reply about not cleaning it, swear out loud then lol.
youre right it sucks. would be easier to take it to the servo put the pump nozzle down the middle and blast 10L through it into a bucket.

mydmax unfortunately i didn't look close enough after the 80k service from the isuzu dealer but after doing it the other weekend i dont think it had ever been done, all the harness connectors on rocker cover were intact and hadnt been cut to remove, all the valves were tight except no.4 exhaust.

the provent was connected properly and will be again, i tested it out by blowing through it and then blocking the outlet and blowing again to test the over pressure valve. it wasnt too restrictive, but like i said before any filtration system is more restictive than a 20cm long piece of 16mm i.d. pipe

i haven't restricted the egr, originally i thought it was a bit of a waste of time as the hole you need to avoid fault codes still lets enough exhaust gases in to make a mess anyway and the plug in chip on the air intake temp. sensor just scared me so i didn't do that either. my plan was to install the provent for a while until out of warranty then clean the intake, get an ecu remap with egr delete.

i was going to start a new thread but: egr. i cant afford a remap for a little while, but in the mean time i can afford a blank plate and cheap ebay obd2 code reader error delete. if you guys think its worth doing, ill do it. should i get the plate with the oval hole already in it, or get the full blank plate and drill my own progressively bigger hole until it doesn't fault anymore? also any safe way to clean the intake without removing it?

Author:  Danno [ Sun Nov 18, 2018 7:56 am ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

Yep, cleaning that filter is not for the faint of heart, I tried everything...turps, petrol, prepsol, Supercheap degreaser in the red can (best degreaser ever) and even dishwasher powder detergent and after hours came to the conclusion that it was an awesome waste of time and part of my life I was never going to get back..

Just get a plate with a hole in it already whatever shape as it's the right size and believe me you don't want to be taking it in and out to enlarge a hole, it's not hard but not necessary. You could do the cable thingy to turn it off but I wouldn't recommend that in the DMax as I believe (but could be wrong!) in the DMax the ECU uses the temp reading from the MAF that the cable fools for other things than just whether or not to open the EGR. My current car the temp sensor on the MAF is only used for EGR operation and a 10 cent resistor turns it off permanently and instantly improves the fuel economy by 1.5 to 2L per 100... You could try it though, it's only a matter of figuring out which wire it is and putting in a resistor.

For all those wondering about the EGR cables sold by Munji and the like on ebay for about 150 bucks they are simply a 10 cent resistor inside a plug your paying $149.90 for a $5 plug ;)

Author:  4jj1 [ Wed Nov 28, 2018 5:03 am ]
Post subject:  Re: dmax valve adjustment , rocker cover gaskets

had the provent back on for a few weeks and no vapour leaks, happy......................

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