L18 engine rattles - turbo oil pump conversion (Read 626 times)

[Talking Hoarse]

After any ideas you may have please. I posted a similar thread on Wills forum last year but this has developed a little.

My old Bluebird 910 has the L18S engine - and has done just 44,000 miles. There are absolutely no signs that it has never been molested (or overheated etc) apart from routine maintenance & my changing the water pump.
It starts up readily whether cold or hot, and appears to be very healthy. It sounds brilliant when running whether hot or cold, ie no undue clatters or rattles.

But when I restart the engine once hot, it has always clattered away like an old timer - sounding to me maybe like lots of cam clearances too wide or the timing chain rattling. This eases off after a few minutes of running. This improved a little after swapping to an aftermarket fuel pump.

However over the past few months, when lit up from cold & after standing for a day or so, the oil pressure lamp takes a long time to go out. This is accompanied by rattles & rumbles from (bottom of?) the engine. However if I crank the engine over for a minute or so (with the coil disconnected) - until the oil lamp goes off - the engine starts up quietly (and I do that whenever I am able to).

I have changed the oil several times to no avail (using 10-40 and latterly 15-40 semi synthetic - it may be a little better on the latter), and have tried several oil filter types (currently using genuine Nissan). The oil filter housing does have a (anti drain?) tube that fits inside the filter (the filter on these later engines hangs upside down so oil drains).

I dont think that the engine is due a rebuild or any bearings (at least not yet) - but should I replace the oil pump in the meantime? If so, should I /can I find a high capacity or high pressure pump (I am guessing maybe auto L24 etc models may have had an upgraded pump?).
Should I be using 20-50 oil or a Wynns like additive instead? Is there an easy way for me to fit an oil pressure gauge temporarily so as to verify the oil pressure? (I am guessing that is a part of the tale).

Any thoughts, wisdom or advice please? Ed

[datman]

The brand of oil filter can have a huge difference. Some have anti drainback properties and some don't, what brand are you using and have you changed it recently?

[Talking Hoarse]

Sept 20, 2012 13:19:57 GMT 1 datman said:

The brand of oil filter can have a huge difference. Some have anti drainback properties and some don't, what brand are you using and have you changed it recently?

Yes - the oil & filter have been changed very recently.
Over the past year or so I have used: Unipart (GFE300), Mann (W920/81), and latterly Nissan (A5208W1106) - all from pukka suppliers (the latter from Nissan dealer of course).
At least the 1st 2 are said to have drain back valves, but the noises are about the same regardless of the filter, maybe slightly worse with the Nissan filter but that might be the clatter getting worse of course.
I have changed the oil with each filter change (ie 3x despite doing just 5 or 6000 miles). I always drain the old oil thoroughly, and crank the engine on the key to get the oil circulating before letting the engine light up etc.

[Talking Hoarse]

Perhaps this would be an answer:
www.autoenginelube.com/ordernow.html ?
Although I would rather spend that money on resolving the root cause of course.
I saw something like this for the 1st time very recently - in a MG Midget "Atlantis" (an ultra rare 70's midget conversion - fitted with Ford running gear) & used for classic rallies and autotests. No room for dry sumping in a Midget. I saw that the canister maintained 40psi even after car was parked for 20 minutes, and is said to maintain oil pressure for a minute with the engine inverted & running.
Ed

[Talking Hoarse]

Just to run with the oil pump (as I guess something is allowing oil to drain back into the sump and it then takes a short while for the pump to distribute the oil around the engine etc). I would recon or replace this anyway if I was doing any bearings.
However my "childs guide to Bluebird parts" shows the pump part number as 15010 21001. I gather that there is also a high capacity pump (listed for 6 cylinder turbo I think) - part number 1501 S8000 that is 5mm longer and should also fit.
Anyone got experience of swapping these pumps?
Is the latter interchangeable and a good idea?

[Al Ramone]

i know that the 280zxt oil pump is sort after, even second hand.
the guys turbocharging their LD28 diesel engines are asking for em.

I'd have thought the standard pump would be fine if everything else was working properly.

modern synthetic oils are much better at protecting engine internals then the older stuff. they also are thinner which means the oil pressure is slightly lower then with normal old fashion oil.
this is a plus as it means less drag so more power and better economy. how much better is debatable.

i guess this means the oil drains back out the engine oil ways much more as well, meaning there's less oil on start up perhaps?
how well these modern oils work in old engines, where tolerances are not so close, as well as the engines having a bit of wear could be an issue?

you can fit a mechanical oil pressure gauge easily, it will be connected to the oil pressure light sender hole in the engine block.
but as i said, modern oils will show a lower reading then you might think is "right"

[Talking Hoarse]

Bump - any other thoughts or suggestions before I invest in a new oil pump?

[datman]

Never heard of having to replace one of those oil pumps. I would a: make sure it hasn't got a taller than standard oil filter on it, the early model had a bigger filter but it sat horizontally not vertically.

b: Try another brand. I had Blueprint filters on my TD42 engine and it took about 8 seconds for the light to go out. Changed to another brand, I forget what, and it took 3-4 seconds.

[Talking Hoarse]

Whilst investigating oil pumps for my Bluebird, I found that 6 cylinder L series engines are often used in Beauford cars.
The attached article is from their club magazine and concerns a pattern high capacity pump (as fitted to L28 turbo's) made in & available from Taiwan, and how to fit maybe without removing the distributor.
Yes - I know its not genuine Nissan!
I am awaiting one of these pumps myself and will of course report any feedback I have.
My thanks and acknowledgement to the editor of the Beauford club magazine for allowing me to post this article.
If you want the pdf emailed just post or pm me.
Ed

Attachments:

[Talking Hoarse]

I received my pump from Excellence in Taiwan yesterday, and fitted it this morning. I followed a combination of the instructions from both Haynes and the Beauford club magazine article attached.
Just as a recap - the L18S engine in my Bluebird has been clattering a bit on start up whether hot or cold, and the oil lamp could take a few seconds to go out whilst the engine was rattling. The oil pump I bought is a high capacity pump I understand as fitted to the 280Zx turbo.
I think that the key to swapping the oil pump “the easy way” is to stop the drive shaft (that is shared with the distributor) from dropping out of engagement. I decided against using Blu Tack to stick the distributor shaft to this drive shaft, as it is oily (and so doesn’t stick well) and I do not want to risk dropping foreign material inside the crank case.
So instead, I timed the engine up to the TDC marks, with the rotor arm pointing at the HT lead for No 1 cylinder etc. I marked the distributor position on its backing plate with a hacksaw notch to aid speedy reassembly. With the distributor removed again, I used a crocodile clip from my battery charger on the end of the drive shaft in an attempt (successfully) to stop it dropping when the oil pump was removed.
Then the car was lifted up, the splash shield removed, and with some trepidation, the oil pump was unbolted and lowered, allowing it also to twist ant-clockwise as it came off. Part of my caution was that I was unsure how much oil would escape – it was minimal despite not draining the oil (but a tray is needed just the same).
I then matched the driveshaft position of the new pump with the old unit and primed the pump with some oil. I did use the Blu Tack to retain two of the mounting bolts in the new pump that – on my car – are constricted by the anti-roll bar. A new gasket was lined up and the pump eased into place.
The distributor was then refitted, marks lined up, and the engine cranked until the oil lamp went out. Then the moment of truth – with the ignition reconnected the engine started and ran quietly.
As soon as the engine was warm I checked the timing with the strobe (it was back where it had started off at 10 degrees), checked for oil leaks and refitted the splash guard.
Result – it is still early days but the engine runs much quieter, both cold and hot. It doesn’t rattle when started up now, although the oil lamp still takes up to 4 or 5 seconds to go out – time will tell.
Ed

[Talking Hoarse]

Progress.....
I have fitted a Taiwanese hi capacity /280ZX oil pump (see the oil pump thread I wrote up recently) and all is much quieter indeed. Early days but it seems to still take 5 or so seconds for the oil lamp to go out, but at least without the worrying rattles.
Next step - I will revert to a Unipart oil filter (in place of the Nissan one at the moment) next time I change the oil.
I might even take the old pump apart to measure it for wear.
Ed

[Al Ramone]

how did the replacement oil pump look? cheaply made?

how much was it and where did you get it from?

[Talking Hoarse]

Oct 9, 2012 19:16:41 GMT 1 Al Ramone said:

how did the replacement oil pump look? cheaply made?
how much was it and where did you get it from?

Hi Al
£50 shipped (took less than 1 week). From:
www.ebay.co.uk/itm/300686721070?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

(I was quoted about £90 for a standard Nissan pump from dealer (after a little discount), but would take several weeks, and more again for a recon pump via a Datsun engine specialist /tuner).

I had exactly the same concerns, that is why I researched before spending (and ended up contacting the chap from Beauford club as he had bought 2).
It looks every bit like the one I took off (only clean), weighs & feels the same. In fact mine looked just like the image on Ebay, (well nearly my gasket needed flattening out .....). I haven't dismantled the pump but there is absolutely nothing to suggest to me that it is less than pukka. Of course only time will tell whether it will work for 29 years like the Datsun one did .....
Ed

[30psi]

Personally I'd now be inspecting the bearings. Do you drive the car hard?

[kgc210]

Would be interesting to take the ebay pump apart to check the dimentions, as the "Turbo" Oil pump has bigger rotor thingy compared to a standard one to give it more volume.


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