Oil circuit

Discuss (and cuss) the Nissan LD-series OHC Six diesel engine, popularly available in the US in 1981-83 Datsun/Nissan Maxima Sedans & Wagons.

Moderators:plenzen, goglio704, glenlloyd, Nissan_Ranger

Post Reply
Pascal
Posts:13
Joined:13 years ago
Location:Belgium
Oil circuit

#1

Post by Pascal » 13 years ago

Hello,

It is official now, I've got no oil pressure at all.
I've taken away the bolt where the oil pressure sender normally sits, and the bolt that connect the oil circuit to the vacuum pump, and there is no oil that comes out of either opening, even after one minute of cranking the engine (I removed the glow pulgs for doing that: no compression is easier for the start motor).

My thinking:
1) The oil pressure sender sits before the oil filter, so even with a clogged oil filter and a stuck bypass valve I should get oil out of the opening for the sender.

2) The oil pressure regulator (valve) bolow the oil pump should never block the oil circuit completely.

3) Even a terrible worn pump should be able to get some flow in a open system (meaning without counter pressure).

4) Can the pump be mechanically be disengaged from the crankshaft, broken spindle/shaft?

5) Or is it the "strainer assembly" that is broken of and that does not suck up the oil (I've checked the oil level of course)?

What would you tackle first bearing in mind that I don't have spare parts readily available like gaskets or pumps etc., or could I do some more testing?

Pascal

User avatar
asavage
Site Admin
Posts:5351
Joined:15 years ago
Location:Duvall, Wash.
Contact:

#2

Post by asavage » 13 years ago

Both of my running LD28s ('82, '83) take quite a long time after starting, for the oil pressure warning light to go out. At cold idle, the '82 can take up to five seconds to extinguish the light -- an eternity! Others have noted similar intervals.

Cranking speed is 1/4 to 1/2 the idle speed.

We don't know which oil filter system your conversion has. Are you operating with a new oil filter? If so, I would repeat your one-minute-cranking test, at 15 minute intervals. It can take a long time to fill a dry oil filter at 250 RPM on an LD28.

Take a look at the 1983 oil filter adapter in this post. If your adapter has this extra line, it has the (better) 1983 dual-filter setup. Also see this post for more details on this filter.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

Pascal
Posts:13
Joined:13 years ago
Location:Belgium

#3

Post by Pascal » 13 years ago

I found out that the oil pump has a crack on the underside, where the oil pressure regulator sits :P. So the pump sucks false air instead of oil.
This is because the front diff of the land rover hits the oil pump when the suspension is fully compressed. I will lower the stop for the supension.
I need to locate an oil pump. Nissan asks 300 Euro for it (405 USD) :shock: .

Any suggestions? :?
Is the same pump used in more recent engines, because I found a shop selling second hands parts, but they are at least cars from the 90's?

Pascal
The LD28 I have is installed in a Land Rover Series 2A wheelbase 107inch of 1967.
Previous owner thinks it comes from a Datsun Laurel.

goglio704
Posts:726
Joined:15 years ago
Location:East Tennessee

#4

Post by goglio704 » 13 years ago

Pascal,

It would be hard to say whether later model parts would fit. For us here in the US, 83 was the last year for the automotive LD 28. :cry:

My guess would be that they would fit, but that is all it is - a guess. :wink:
Matt B.

83 Maxima Sedan, LD28, 5 speed, white, 130k miles. My original Maxima.
83 Maxima Sedan converted from gasser, LD28, 5 speed, 2 tone blue, 230k miles
82 Maxima Sedan, LD28, 3 speed auto, 2 tone Gray/Silver, 140k miles
81 810 Sedan, LD28, 3 speed auto, rust, rust, and more rust!

2005 Jeep Liberty CRD

User avatar
asavage
Site Admin
Posts:5351
Joined:15 years ago
Location:Duvall, Wash.
Contact:

#5

Post by asavage » 13 years ago

I'm fairly confident that the LD28 oil pump is the same or very similar to the 280ZX turbo pump.

I have what I think is a brand-new LD28 oil pump in storage (from eBay). If that's true, you should be able to buy it where you are fairly easily.

I'll check today on the part number.
[later]
Nissan has different illustrations and part Nos. for the L24e and LD28 pumps.
Image

I think you can bolt either one on though.

LD28 (all years) is listed as 15010-P6600, USD$80
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

Post Reply

Who is online

Users browsing this forum: Google [Bot] and 3 guests