New motor using/losing oil - thinking fuel pump?? Ideas?

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Bala
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Bala » December 23rd, 2013, 10:00 am

The brand of oil will not be your problem here, it would not matter what you put in now it will not fix it.

It really is a LOT of oil!!,I find it hard to believe it is not showing on the plugs or out the exhaust, and the PCV hose/crancase breather hose.

Trav Man
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Trav Man » December 23rd, 2013, 6:48 pm

I just realised that I didn't mention that it was fine for about the first 8000kms before this started happening.
But I am pulling the motor out around New Years and will go from there as the Handbrake said all good as she was giving me some money for Christmas to get my motorbike back on the road so I can use it on the motor instead but I think I'll be sent to sleep in the cave while I'm at it :ooh:

Also I do appreciate and thankyou guys for your help with this. :D

Shaker4x4
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Shaker4x4 » December 27th, 2013, 10:09 pm

Any time Trav, it's why we join forums, to help each other out and share information as we gather info from others in the process.

Perhaps take it to a mechanic and get him to diagnose the real problem so you aren't pulling it apart and wasting time and money. Don't take my word for it as I can't see the motor nor put any equipment to it from my PC chair. I just want you to be sure before throwing money away. During those 8,000kms, perhaps after rings bedding right in, that's when you noticed chronic oil consumption. During the running in process, it's normal to burn a bit more oil but that should have stopped long ago. All of us are guessing based on what you've told us mate. Sorry we couldn't be definite though. Ask Allen from Terrain Tamer. He's a guru and would be happy to give you a little advice if you can steal a bit of he's time. He may also tell you to bring it in or take it to be looked at elsewhere as I have lol.

I'm no mechanic hey :P

I could imagine it at home. "Merry Christmas honey... while you're opening that present, I have another present for you... the engine may need to..."

Shakes.

Trav Man
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Trav Man » December 28th, 2013, 10:29 pm

That's all good mate as I am pulling it out Monday and hopefully find the problem then as talking to my mates mechanic/engine builder he's say defiantly rings as I was given/told the wrong ring gap eg: too small :irked: so we believe that it has F@#$%D the rings and hopefully not the bore but will have to wait until then to confirm. :ooh:

cmar
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by cmar » December 30th, 2013, 9:01 am

Mate, have you run it exclusively on gas since rebuilding it? A motor run exclusively on gas often will not seat the rings properly, due to the increased amount of oil often found on the cylinder walls in a gas engine. This is because in a petrol engine there is always a certain amount of oil wash down from unvapourised petrol. Because gas is a dry fuel this oil just sits there and prevents the rings from properly beffing in. The IMPCO gas installation manual actually used to recommend coating the bores with a weak solution of Bon Ami in kerosine or diesel on a rebuild so that the rings would seat properly in a gas engine. When I rebuilt my (gas) engine in my Bronco many years ago I couldn't bring myself to do this (although it supposedly does no harm) so I ran it on petrol exclusively until the first proper oil change ie 10,000 Km and used a straight non -friction modified mineral oil for the first oil load, (Castrol XL 15-40) if I recall correctly. After that I went back to my usual Castrol RX Super. That engine never had oil consumption problems and 10 years later was still running well.
Haven't owned a 2WD since 1982.

Trav Man
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Trav Man » December 30th, 2013, 3:06 pm

CMAR: I run it in on petrol for the first 5000kms with run in oil then went to gas as I haven't had any issues before on other engines I had rebuilt.


Well she's now in pieces an we were all wrong :redface:
I suspected #4 when the head come off
Image
so that was the first slug to come out and ummmmmmmmm yeeeeeeeaaaaaaaaaaahhhhhh not the rings :eek:
Image
all the rest were fine and I double checked all the ring gaps and they're all spot on perfect.
So I'm heading off to try an organise some new slugs and rings and thanks again every one for the help.

Trav Man

Shaker4x4
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Shaker4x4 » December 30th, 2013, 3:23 pm

Wow! I've not seen that before! Did it ruin the bore and if so, is a re-bore and new piston set in order now? You wouldn't get away with honing out damage if that was scoring up and down?

Reports please. This is a really good lesson. Look at the compression chamber on number four though, no wonder the plugs looked fine...

We were almost on track, this is not overly common. If the ring gap was too small and too tight in there from new, it may have caused this for sure!
Last edited by Shaker4x4 on December 30th, 2013, 3:26 pm, edited 1 time in total.

mydmax
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by mydmax » December 30th, 2013, 3:24 pm

Trav Man
It looks as though there was/is a ridge at the top of the bore and it has as usual worn as a rounded edge lip ie concave and the new rings are dead square and so it has hit the bore lip and broken the ring and piston land. If you have any lip at all it must be removed or the same will happen again.
Do you remember any time when it might have had a good rev and afterwards the oil problem was noticed? A good rev with a lip on the bore often will smash the rings and other bits too.

A lip on the bore can cause that as it has forced the ring hard down on the land and broken it clean off. Looks to be on the thrust side of the bore and piston as that is also the lip side if any.

Hope all is together again soon.

Shaker4x4
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Shaker4x4 » December 30th, 2013, 3:28 pm

But they refurbished the cylinders mydmax, but what you say makes more sense, it's been jamming up top repeatedly more than likely. Not de-ridged correctly or at all?

mydmax
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by mydmax » December 30th, 2013, 4:39 pm

I know lots of people say they fully rebuilt their engine but it seems there are degrees of fully rebuilt and attention to detail is vital for best reliability. Of course failure can happen with anything, it is just best to try and minimize trouble.
If the cylinders had been rebored, then the ridge shouldn't be there and maybe if no ridge the piston has grabbed to cause that.
A sudden ingest of water or oil and a quick crank over, can also add undue pressure to the rings and piston lands.
Just strange it seems to be on the thrust side of the piston where a ridge can have it's effect.
Maybe Trav can shed more light on it all.

Either way it is a sad day for Trav.

Trav Man
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Trav Man » December 30th, 2013, 6:32 pm

I had it rebored to 20 thou over with new slugs, ring, bearings, timing gear etc etc so I rebuilt the full engine hence the reason why the wife flipped her ***** and I'm sleeping in the cave with the motor tonight but that's okay as the beer fridge is stocked and I'm on the old lap top :lol:
I haven't had it off road since the rebuild as I was about to go but that's when the oil burning issue arose.
All I can put it own to is a faulty piston as there is no ridge/lip at the top of the bore as it was rebored.
I did have the block decked due to pitting around fire ring #4 and there was about 0.3mm clearance from piston to deck clearance if that makes any difference and the head had been decked previously as well.

Shaker4x4: No thankfully the bores are okay so a quick hone new rings and slugs and all should NO NO NO ALL WILL BE GOOD

Trav Man
Last edited by Trav Man on December 30th, 2013, 7:30 pm, edited 1 time in total.

Bala
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Bala » December 30th, 2013, 7:04 pm

I have never seen this before but did a quick google,

"piston ring land breakage"

It looks like a lot of cause is detonation, and by the looks of it, its not an uncommon problem.

You need to find the cause or you may end up doing this all again.

mydmax
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by mydmax » December 30th, 2013, 8:27 pm

Perhaps it is detonation and either the timing is incorrect or the fuel is too low a grade since the engine will now have more compression than before. A knock sensor would be an ideal extra to have.

Trav Man
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Trav Man » December 30th, 2013, 8:44 pm

Timing it could be as it is over head cam and with both the block and head being decked it has thrown the cam timing out of whack and I now have an adjustable cam gear to put in it to correct it as I thought about it just before it started using oil and have had it here for a few weeks and now going to install it to correct the cam timing as my mate has a cam degree wheel I can borrow to set it right.
So with the higher compression should I run the high octane fuels ????

Shaker4x4
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Re: New motor using/losing oil - thinking fuel pump?? Ideas?

Unread post by Shaker4x4 » December 30th, 2013, 8:49 pm

What a good thread and some brains at work too. Trav, it had better be all good because you'll be sleeping in someone elses cave drinking their charity beer if this goes south on you haha. detonation Mydmx sounds likely too. Smart man. Then again you cheated with some of that experience stuff somebody let you have. someone chasing savings by running low octane fuel and LP gas. Would LP gas cause detonation?

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