Possible Engine Failure...please Help Any Ideas?!?!

[Redliner007]

hey guys ive recently had more issues with my 30 just wondering if someone could help me out... recently the motor after an hour or so highway drive started to knock, I just can't understand why...initially i thought it was the hydraulic lifters or something as it sounded like it was coming from the head,it was fairly similar to the sound I heard when i first done the start up after a while of warming up it had gone away. I can't understand how it maybe a bottom end knock, as everything is acl race, forged pistons, shot peined rods, n1 oil pump etc motor was fully balanced and had a run in tune. I only had a standard rb20det turbo on there as I had just finished running it in and only just done the oil change. I cant understand what it may be the car did not over heat on the long trip or lose any power. Thinking back i do remember when i was bringing the car back from the tune at traffic lights the oil pressure droped dangerously low and when i gave it a few revs it went back up again so i kept the revs up on the drive back home, but since then it has never happened again (this would have been in the first 50km or so of fresh build).

I do not know what it can be, please help?!?!? The oil that i'm using is Penrite HPR 10

I've done a compression test on the motor and got between 110-120 across all cylinders, it may be slightly low maybe because of the pistons ive used or perhaps the head gasket?

any ideas or suggestions will be much appreciated I just hope I don't have to pull the motor out again.

Edited February 22, 2010 by Redliner007

[todoom]

hey guys ive recently had more issues with my 30 just wondering if someone could help me out... recently the motor after an hour or so highway drive started to knock, I just can't understand why...initially i thought it was the hydraulic lifters or something as it sounded like it was coming from the head,it was fairly similar to the sound I heard when i first done the start up after a while of warming up it had gone away. I can't understand how it maybe a bottom end knock, as everything is acl race, forged pistons, shot peined rods, n1 oil pump etc motor was fully balanced and had a run in tune. I only had a standard rb20det turbo on there as I had just finished running it in and only just done the oil change. I cant understand what it may be the car did not over heat on the long trip or lose any power. Thinking back i do remember when i was bringing the car back from the tune at traffic lights the oil pressure droped dangerously low and when i gave it a few revs it went back up again so i kept the revs up on the drive back home, but since then it has never happened again (this would have been in the first 50km or so of fresh build).

I do not know what it can be, please help?!?!? The oil that i'm using is Penrite HPR 10

I've done a compression test on the motor and got between 110-120 across all cylinders, it may be slightly low maybe because of the pistons ive used or perhaps the head gasket?

any ideas or suggestions will be much appreciated I just hope I don't have to pull the motor out again.

I had a noise in my 30 engine it was quite at idle and it got a knock a 2000rpm and it stayed the same all the way through the rev range. I pulled the engine out and found the it had spun a bearing, I had a fully forged bottom end and all the bearings. I also had a broken oil pump and it was an N1 and i still had good oil pressure all the time.

[Duncan]

sounds bad to me....the first 1000klm of any motor are the most likely time for it to fail.

i'd suggest getting a good mechanical oil pressure gauge on there to check what is happening, but don't drive it anywhere or run it.

most likely a bearing clearance problem, assembly mistake, not cleaned properly or some oil pump failure.

I hope that you had a single mechanic responsible for the whole build, because getting warranty on engine builds can be tricky

[Redliner007]

Hey guys, I got told by a couple of people to do a leak down test on the motor (im not sure how to do this). In reply to Todoom just a question you know how you spun your bearing was the motor under any kind of load at all? It could possibly be my oil pump as I did use a N1 oil pump but in the rush i did not fit the collar to it expense mistake maybe??

As for assembly to Duncans comment well i was present there my mechanic friend was the one who put the bottom end together and I was there helping him assemble the whole thing...so yeah no warrantee there as it was more a favour unfortunatly lol I havn't driven it since it got home only started it a couple of times not running it for very long.

I guess all this is pointing towards me pulling the motor out and actually looking into it that way?? Are there any other possible tests or anything I could do before having to rip the motor apart? Is it possible to spin new bearings also?

Thinking back I did only use 1 1.5mm Restrictor on the block could this have lead to the possible bearings being F****ed

Edited February 23, 2010 by Redliner007

[payback21]

Hmm doesnt sound good. As Duncan suggested, get a good oil pressure gauge on the engine and see what is happening. It would be the first thing i would be doing as a test.

[GTScotT]

as stated above, sounds like oil pressure is an issue... you already mentioned you lost pressure once already.. if it were to lose pressure for a while it would result in damage capable of making a knock sound that only appears when oil pressure drops slightly.

the theory i am suggesting is that you now have a clearance issue on one of your bearings which is only evident when oil pressure OR flow is low a gap is created and you hear the noise.

[STATUS]

or the pickup could be loose. Could be a myriad of things all of which the results could suck if left too long..

Best bet is to drop the sump and look for play in the big ends (conrod) and pull a few main caps off too just to be sure. Thi swill tell you what is damaged.

[Redliner007]

in replies to the oil pressure issue, my question is wouldn't the knocking sound have come up alot earlier? As i mentioned that the pressure dropped within first 50km or so. But yeh looks like i will have to get the oil pressure gauge and perhaps drop the sump see whats going on.

TRENT you said "Could be a myriad of things all of which the results could suck if left too long.. " so pretty much i should get onto this as soon as possible? This did happen roughly a month ago now :S

[Redliner007]

Hey All, I just want to thank you all for helping me with suggestions and ideas I really appreciate it guys

[GTScotT]

well yes, it could have come up earlier, yet as ive suggested it could be intermitent and pressure/flow dependant. also the oil pickup as trent said could easily do that too, i have also heard of bad gaskets on oil pickups causing all sorts of issues.

so as stated, drop sump and inspect... but if not confident please get a mech you TRUST to do it, you need to retorque everything 100%. the original builder would be preferable for the job.

[The Dan]

You could always do an oil test first. But any time someone suggests that, it always the last thing that happens

Chances are one of the bigend bearings has failed. If it happens in the first 1000km then you can pretty much look straight at your engine builder.

If one wasn't torqued correctly then it could be something simple like that. Either way, not a good situation

[GTScotT]

You could always do an oil test first. But any time someone suggests that, it always the last thing that happens

elaborate, sounds like valuable info

[The Dan]

An oil test is something that all of you should be doing as part of routine maintenance.

They cost about $35 per test, results in about 48 hrs (usually) and they tell you everything - even if you have a dirty air filter

You can pick up an engine failure before it happens. I have done an oil test when pressure dropped 5psi. The test showed raised levels of lead and copper, we drove the car for a week and did another test, the levels of copper and lead increased so we pulled the engine down. Scuffing on the bearings and slight wear on the thrust bearing.

Absolutely no crank damage, bearings were all still intact but all showing signs of wear. We were able to get to it before it did any damage.

Unfortunately for this one, there is a knock, whcih means the damage is probably already done.

[GTScotT]

Thanks champ.

[The Dan]

Contact Australian Laboratory Services

ALS Wearcheck

[GTScotT]

How much do you usually need to send em? can you simply mail off a sample or need to see them in person?

[todoom]

Hey guys, I got told by a couple of people to do a leak down test on the motor (im not sure how to do this). In reply to Todoom just a question you know how you spun your bearing was the motor under any kind of load at all? It could possibly be my oil pump as I did use a N1 oil pump but in the rush i did not fit the collar to it expense mistake maybe??

As for assembly to Duncans comment well i was present there my mechanic friend was the one who put the bottom end together and I was there helping him assemble the whole thing...so yeah no warrantee there as it was more a favour unfortunatly lol I havn't driven it since it got home only started it a couple of times not running it for very long.

I guess all this is pointing towards me pulling the motor out and actually looking into it that way?? Are there any other possible tests or anything I could do before having to rip the motor apart? Is it possible to spin new bearings also?

Thinking back I did only use 1 1.5mm Restrictor on the block could this have lead to the possible bearings being F****ed

The motor was just under normal driving conditions when it spun i would suggest a crank collar and put the billet gears in the pump as the standard ones are very weak.

[The Dan]

How much do you usually need to send em? can you simply mail off a sample or need to see them in person?

It's about 100ml - 150ml and comes with it's own return postage. You mail it off and they email the results

[The Dan]

1. The leak down test is not going to tell you shit about the oil pressure or the knock

2. 110 - 120 psi is rediculous. Should be up around 150-160. If you have some kind of special setup or whatever they can be as low as 140psi

3. What did your friend use to measure the bearing clearances and who did the machine work on the crank and block?

[Redliner007]

we had an engineer who did all the machining work, we did use him in other engine builds and he all good. To be honest I cant remember if we measured the clearance at all of the bearings.

Sounds like the oil test is the way to go. I wonder if i could find someone local to do this for me. Is there a special name I should be looking for in the directory? I have spoken to my mate about the situation and he is happy to help its just that he has started a new job and is working 6-7 days so may be a long wait before anything even gets looked at. I'm not prepared to wait too long as I don't have a car anymore and him being in a different town isn't all that much of a help either lol.

If i were to pull the motor out AGAIN i'll probably be considering doing the following:

As Stuart mentioned the billet gears... I wasn't aware of this originally but hey if it helps with oil control thats a + in my books

also getting the collar done for the oil pump

may even consider getting forged rods if the pockets let me

Is there anything I should also consider doing when its apart?

also is 1 oil restrictor alright for the block? I didn't want to restrict both the oil galleries as I didn't want to staff the head too much.

Also what torque specs did you guys use for the bottom end? We used the r32 gtr settings I wonder if this could have been an issue also?

Edited February 23, 2010 by Redliner007