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rebuilt engine questions, to buy or not?


innerware

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Ok so I was eating a bit of coolant as of last week. Couldn't find the problem on my 180k mile stock 78 280z engine. That is untill this morning. I have been checking for leaks and fluid drops everytime I drove it. 6 miles each way from home to work. Well this morning I checked after I got in to work and saw and smelled coolant. Can't tell where it is coming from so I turn the engine back on and look for leaks. Well, now I notice a bunch of white smoke. I am thinking headgasket or cracked head. What else could it be right? Since the engine is old I don't think it is worth the time in doing the head gasket. I don't drive hard so I don't think the head is warped or cracked. But the real question is this:

 

A guy on zcar is selling his 78 280z engine as follows:

 

Datsun 280Z rebuilt motor for sale - L28

Created 06/16/05

 

Description Rebuilt motor for sale. Decided not to finish the restore project on my '75 280Z(Car is sold). Here is a list of work done and new parts.

 

L28 block w/ N42 head

-New gaskets (whole set, including crankshaft

seals)

-New freeze plugs in block

-New Oil pump, Water pump & Timing chain

-Rebuilt Crankshaft

-New Main Bearings

-New Rod Bearings

-Cylinders bored 2mm + honed

-Flathead Pistons for more compression

(stock is about 8.3:1, now closer to low 10's:1)

-Head was baked to take out any warpage, then

cleaned and resurfaced

-New valve guides and valve seals

-New performance camshaft with higher lift &

duration (Intake .441; Exhaust .441)

-Reassembled to recommended torque specifications

 

Engine has been garage stored and well taken care of. $1700 worth of work done including parts(I have receipts). Comes with intake manifold, injectors, exhaust manifold, and throttle body. Asking $1100/OBO

 

Located in Santa Cruz, CA

State California

Phone

Price $1100.00

 

 

If your still with me, and it is still for sale... Does this sound ok to you all? It is close enough to me (2hour drive) Should I buy it? Is the price good? What is this head combo good for? Are the rebuilds he did good? Pros and cons? All opinions are more than welcome.

 

Thanks ever so much as always,

Kyle

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Ok so I had a co worker look at it and he thinks the smoke is fuel related. Regardless I am leaking fluid and can't seem to see where. There is some fluid build up on the steering rack bushing clamps, but really can't see where it is coming from. Why would I be running righ all of a sudden? Is it related to the coolant issue?

 

Thanks again, I should just take it in anyway and have a pro look at it. But I thought I would ask incase it is something I could look at too.

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I would definetly do more research first. If you suspect it's a head gasket, a simple compression, or leak down test will most likely determine that. You mentioned fluid in the rack. My first thought would be a water pump. When the bearings start to go, fluid comes out of the "seep hole" on the bottom.

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thanks. Yeah I just don't know. My oil looks fine and my coolant does too. I will do a compression test and see if my numbers are consistant. I need to smog it soon so I was going to get a pre test done anyway. I'll let my mechanic look at it then too. I won't drive it untill then.But if the pump gasket is going where should i see fluid coming from? I didn't notice any from around the pump area.

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Another tip: Take off the oil filler cap and look at the inside of the cap. If it looks like a used baby diaper or some sort of bad salad dressing you have the signs of coolant getting into the combustion chamber and past the rings into the oil. The water vapor gets trapped at the highest spot, the underside of the valve cover and may not show in the oil pan.

 

Small coolant leaks probably won't show up in compression or cylinder leakage but it is a good indicator of the wear on the engine. Good luck.

 

P.S. Coolant smells sweet in the exhaust and burns white, oil burns blue and, of course, gas shows black in the exhaust.

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Thanks,

 

I looked at the filler cap and all was clean. The smoke was definately whitish that came out the back. Although my buddy says he is pretty sure it was because I am running rich. He says the exuast smelled rich. It does look like the block is darker above the oil filter (moist) and I am probably going to need to replace the oil pan filter (small leak). But I can't see any drips or nothing when the car is running. I just noticed some coolant pool at the hold downs for the steering rack (driver side). The radiator is a JTR one with new hoses. I drove it home today and there was the same old power it has had. At least it didn't feel sluggish. My temp stayed right at mid point or just slightly below.

 

I'll let you all know how I fair. But if there are any tips etc that I am missing let me know.

 

Thanks again,

Kyle

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So true about white smoke. Did this car overheat about six months prior? There are many very good ways to remove broken head bolts from the engine block without doing damage to anything. I got a job offer for doing a head bolt repair for a friend's shop. Hopefully you don't have a head gasket problem and it is an external coolant loss.

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Peter what are some good ways to remove broken headbolts? I have a 78 280z (body is junk) and a 77 280z (body is good, engine is junk) the 77 came with a n42 head and the 78 a n47. I've read that the n42 flows better on the intake side, is that true? SO what I'm gonna do is swap engines and swap heads and afraid of the bolts breaking in the process. So, all in the good car (77) will be 78 engine w/ 77 n42 head.

 

Innerware have you tried cheching the temp sensor for leaks? Are you running a L26 enigne or something else? You said you had a JTR radidator, the reason why I'm asking.

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as far as I know the car has never overheated. I did have about that long ago or more a heat sink problem where it would be hot right after restart if I restarted it within 10 minutes. That lasted a little while then just cured itself. It has been such a champ since then. Never getting too hot (middle of temp gauge) even in traffic etc. Well, lets hope it isn;t too bad. Is it cheaper to get it rebuilt or swap it with an allready rebuilt motor? I know it would be certainly quicker to do the latter.

 

Thanks

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