Higher EGT's after engine rebuild

Hey Guys,



Recently bit the bullet & got my ZD30Di fully rebuilt by an engine reconditioner, installed engine back in the car with everything as per before the rebuild.

But on the first drive I noticed my EGT's would get to 500 degrees quite easily on small hills.



After the drive I cleaned the MAF, put a new air filter in, checked over all the hoses & there doesn't seem to be any boost leaks/all the hose clamps are tight.

Also lowered the Tillix valve ramp a touch & increased the needle valve boost pressure to 16/17psi, this seemed to help a fair bit.



But driving around town I'm still find it sitting between 280-385 degrees on the EGT gauge, but the temperature drops fairly quickly when stopped or idling to around 220-250 though.



I also have noticed the car smells a bit sooty/unburnt diesel just after you turn it off.





The car is a 2005 ZD30DI with the following modifications/parts replaced:

-Engine rebuilt with every part replaced or refurbished (All genuine Nissan parts used except pistons which weren't available in 0.5mm oversized)

-Tilliex boost controller

-Cross country top mount intercooler with undermount fan (Cleaned out any oil residue before installation)

-EGR blocked at manifold & intake

-Provent 200 catch can

-high flow airbox & stainless snorkel

-K&N air filter

-Spill line mod on the injectors/ fuel pump

-Silicone intake pipe

-Aluminum radiator

-6 month old genuine Nissan MAF

-Year old genuine Nissan Injectors & Rebuilt fuel pump

-New genuine Nissan exhaust manifold

-Inconel exhaust studs for manifold/turbo/dump/egt tube

-Brand new genuine Nissan gaskets used throughout





Is there anything else you guys can recommend to check/replace that may help bring down the EGT's/reduce the possible over fueling?







Is it possible that the cams/fuel pump might be a tooth out causing the high EGT's? (not sure if it just wouldn't start if it was a tooth out of time?)









Any help much appreciate!



Cheers guys!

The engine will be tight being rebuilt. Give it some time to run in and you will find the EGTs will come down.


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Quote:

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Originally Posted by GUFLEX

Hey Guys,

Also lowered the Tillix valve ramp a touch & increased the needle valve boost pressure to 16/17psi, this seemed to help a fair bit.

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What do you mean here:
lowered the Tillix valve ramp a touch? Not sure how you have adjusted the Tillix/needle for max boost.

For Info: Try setting Tillix (boost controller) in conjunction with adjusting the needle valve to achieve the max boost say 16-17psi (w/stock ECU) and note that the needle is to be adjusted so that the VNT actuator rod lever just touches the vane limit stop grub screw with engine @ idle.

Edit: Notice that you are writing in the other place and this is OK as good to get varied advice

Low AFRs (too much fuel can make them run hotter - higher EGTs.
Yes, timing can impact but would say eng rebuild mechanic would knows his job (hopefully).
Suggested the boost control adjustment (first) as poor VNT vane management can cause increased exhaust manifold pressures and resulting in higher EGTs.

Check the hoses going to your Catch can. Sometimes mechanics put them back the wrong way around. This can build up crank case pressure and can cause a number of issues.

Quote:

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Originally Posted by mudski

The engine will be tight being rebuilt. Give it some time to run in and you will find the EGTs will come down.


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Been hearing this from a few people, guessing this might be the case plus needing to re adjust the boost controller to lower the exhaust manifold pressure.

Quote:

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Originally Posted by Bidja

What do you mean here:
lowered the Tillix valve ramp a touch? Not sure how you have adjusted the Tillix/needle for max boost.

For Info: Try setting Tillix (boost controller) in conjunction with adjusting the needle valve to achieve the max boost say 16-17psi (w/stock ECU) and note that the needle is to be adjusted so that the VNT actuator rod lever just touches the vane limit stop grub screw with engine @ idle.

Edit: Notice that you are writing in the other place and this is OK as good to get varied advice

Low AFRs (too much fuel can make them run hotter - higher EGTs.
Yes, timing can impact but would say eng rebuild mechanic would knows his job (hopefully).
Suggested the boost control adjustment (first) as poor VNT vane management can cause increased exhaust manifold pressures and resulting in higher EGTs.

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Apologies has been ages since I fiddled with the boost controller & seems I was adjusting the wrong ones :icon_bonk:

Good tip on setting the Tillix will give it a go this afternoon & try to dial it in properly.


Hopefully the above helps lower the EGT's, if not might get the AFR's checked just incase (Would hate to glaze the bores from over fueling on the break in)

I would assume the engine builder has got the timing right, but if the timing was out a tooth wouldn't the car run super rough? (Currently running quite well except for the EGT's)

Quote:

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Originally Posted by BillsGU

Check the hoses going to your Catch can. Sometimes mechanics put them back the wrong way around. This can build up crank case pressure and can cause a number of issues.

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Checked the catch can lines last night & they were plumbed to the right spots, thanks for the tip though.

G’day GUFLEX Mate,
Are your water temps still running similar as before rebuild or lower on the same test roads you’re now experiencing higher EGT’s?


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@GUFLEX Re manual boost control adjustment - if spool is too laggy, by having the needle valve way too open this will cause higher EGTs when engine is under load hauling.
As said best to adjust needle so that lever just touches the vane limit stop screw.
Suggest U first close needle then adjust Tillix to achieve a target max boost (initially 15-16psi) and then at idle gradually open the needle valve until the lever just starts to drop away from the stop screw. May then want to wind the Tillix in a bit more to raise max boost again - this is fine but once again, adjust the needle valve so the lever just starts to drop away from the stop screw. Check how it goes.
Manual or Auto?

AFR should not have change if ECU was not touched. Stock ECU? or Remap?

Quote:

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I would assume the engine builder has got the timing right, but if the timing was out a tooth wouldn't the car run super rough? (Currently running quite well)

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I would agree mate.

From other read:
10W40 would be fine, just take it easy, do not labour engine (no tow) for first 1000kms (don't rush it) and then drop oil and change filter (@1000kms) then again at 5000kms change.

5000 kms ago I rebuilt my CRD, did not use run in oil, just 10w40 and changed @ 500ks then 1000ks just being over cautious. Oil & filters are cheap in comparison to rebuild.

As @MB mention how are ECTs going and daily check both oil and water levels (especially water for first week or so).

Quote:

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Originally Posted by MB

G’day GUFLEX Mate,
Are your water temps still running similar as before rebuild or lower on the same test roads you’re now experiencing higher EGT’s?


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Hey MB,

The water temps have risen slightly since the rebuild, used to hover at 78-81C around town & rise to 81-86C on the highway in hilly areas

Its sitting more like 80-84C around town now, haven't had a chance to get any highway Km's on it yet though.

Another thing to note is the car has a low temp thermostat (76C from memory) & a large Fenix alloy radiator installed.

Quote:

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Originally Posted by Bidja

@GUFLEX Re manual boost control adjustment - if spool is too laggy, by having the needle valve way too open this will cause higher EGTs when engine is under load hauling.
As said best to adjust needle so that lever just touches the vane limit stop screw.
Suggest U first close needle then adjust Tillix to achieve a target max boost (initially 15-16psi) and then at idle gradually open the needle valve until the lever just starts to drop away from the stop screw. May then want to wind the Tillix in a bit more to raise max boost again - this is fine but once again, adjust the needle valve so the lever just starts to drop away from the stop screw. Check how it goes.
Manual or Auto?

AFR should not have change if ECU was not touched. Stock ECU? or Remap?


I would agree mate.

From other read:
10W40 would be fine, just take it easy, do not labour engine (no tow) for first 1000kms (don't rush it) and then drop oil and change filter (@1000kms) then again at 5000kms change.

5000 kms ago I rebuilt my CRD, did not use run in oil, just 10w40 and changed @ 500ks then 1000ks just being over cautious. Oil & filters are cheap in comparison to rebuild.

As @MB mention how are ECTs going and daily check both oil and water levels (especially water for first week or so).

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Thanks for the advice on the Tillix/needle valve tuning Bidja, had a go at it today (also cleaned up the hose routing/lengths). Got it to a way more stable boost level (no overshoot, boost bounce & set to 15-16psi) but the EGT's were similar to before (maybe a very slight change). The car is a manual & the ECU is stock yet to have a remap.


Planning to drop the oil at 500km for another batch of the run in oil & a fresh filter (have both sitting there), then will swap over to the 10w-40 when it gets to 1000km. Agree that oil & filter is definitely worth doing for peace of mind, Oil & water seem to be staying topped up so far & been checking them fairly regularly. Will continue checking them over over next week & see if the EGT's change.

Out of interest, any idea what EGT's should I be seeing around town?

@GUFLEX Really do not think your ECTs out of the ordinary. My CRD (info only) ECT warm engine range is 86-94 (no tow) - includes hauling and running stock thermostat /radiator.
My travelling is mainly rural and not much in town but would expect EGTs around town be nom 250-300C (but very subjective). From what I understand, it is not good to exceed 550C for DI (hauling).

Would suggest checking AFR to know that she is not running excessive fuel. Maybe eng is too tight but questionable as was not my CRD rebuild experience.

When did you block EGR, understand that this can cause higher EGTs would have to confirm this maybe @phdv61(drops by here occasionally) can help out here. @mudski

Yes blocking the EGR will give slightly higher EGT's. I still think its because the engine is new, things will be tighter than normal. Just make sure the boost control valves are right, if it were me I would wind in the needle valve more to make the boost rise faster, this will assist in lower EGTs, not by much but it will help. Just incase there any lag down low...