Dave W 1971/240Z rebuild

[davewormald]

On 7/15/2023 at 6:55 AM, grannyknot said:

As far as I can tell, the engine has seen light use but a lot of neglect

Did I neglect to mention the neglect? I was actually pretty good with routine maintenance of the old Datsuns, although this one didn't get a tune-up for a long time toward the end. For those who weren't there, I commented to Chis the other day that I had a 2003 Mini Cooper S (great car) prior to my current 2013 model. Mini's recommended oil change interval was 25,000 km. The on-board computer adjusted that distance based on driving patterns. I was driving 150km per day on highways at the time. The longest interval the computer got to was 42,000 km. Mini dialed back their recommendation to 15,000 km (or two years) on the new models, but rumour has it that they only did it because of blowback from their service departments and garages that were appalled by the original recommendations. I'm sure synthetic oil, better filters, tighter tolerances, etc, have a lot to do with these variations. I drive a lot less these days, and do a lot more oil changes. I suspect I'll never see my car again if I don't agree to stay on top of this one. No need to worry. I don't plan to ever let this one go, so I'll behave!

[Racer X]

5 hours ago, davewormald said:

Did I neglect to mention the neglect? I was actually pretty good with routine maintenance of the old Datsuns, although this one didn't get a tune-up for a long time toward the end. For those who weren't there, I commented to Chis the other day that I had a 2003 Mini Cooper S (great car) prior to my current 2013 model. Mini's recommended oil change interval was 25,000 km. The on-board computer adjusted that distance based on driving patterns. I was driving 150km per day on highways at the time. The longest interval the computer got to was 42,000 km. Mini dialed back their recommendation to 15,000 km (or two years) on the new models, but rumour has it that they only did it because of blowback from their service departments and garages that were appalled by the original recommendations. I'm sure synthetic oil, better filters, tighter tolerances, etc, have a lot to do with these variations. I drive a lot less these days, and do a lot more oil changes. I suspect I'll never see my car again if I don't agree to stay on top of this one. No need to worry. I don't plan to ever let this one go, so I'll behave!

The very long service intervals on today’s cars seem excessive to me. Sure, the oils available today are much better than 30 years ago, or more, but today’s car engines rebreathe the stuff that used to go out the crankcase vent into the atmosphere and onto the roadway. They also run hotter.

I always change oil and filter every 5,000 miles, or once a year, whichever comes first.

Oil is cheap insurance.

Clean oil is essential to longevity.

 

Edited July 17, 2023 by Racer X

[grannyknot]

19 hours ago, davewormald said:

I drive a lot less these days, and do a lot more oil changes. I suspect I'll never see my car again if I don't agree to stay on top of this one. No need to worry. I don't plan to ever let this one go, so I'll behave!

Oh that's right, I have the keys to the car in my possession, maybe I should have a copy made ... just in case.

Edited July 18, 2023 by grannyknot

[davewormald]

Oh that's right, I have the keys to the car in possession, maybe I should have a copy made ... just in case.

Good reminder. That's actually the only key to the car. I should get more made!

Sent from my SM-S908W using Tapatalk

[grannyknot]

I got the head back from the machinist today so I can start putting that back together.

 

[madkaw]

Here’s a pic of known FOD . This was done by a small bee bee of weld that found its way in the intake and got sucked in the engine - it’s a long story . That head is still in use on my 3.2 stroker 
Are you going to do anything to the head ? New seats , bigger exhaust valve, unshroud the valve areas. 

[madkaw]

13 hours ago, grannyknot said:

I got the head back from the machinist today so I can start putting that back together.

 

So was this head worked previously ? Are those steel seats ? 

[Patcon]

@madkaw

How noisy was the debris in the cylinder?

[grannyknot]

9 hours ago, madkaw said:

Are you going to do anything to the head ? New seats , bigger exhaust valve, unshroud the valve areas. 

 

There is lots of stuff I'd like to do.😀   The valves are in good shape and so are the guides, also Dave would like to avoid mission creep, he is looking for a weekend driver that is as close to stock as is cost effective, gotta stay in budget.

[madkaw]

1 hour ago, grannyknot said:

There is lots of stuff I'd like to do.😀   The valves are in good shape and so are the guides, also Dave would like to avoid mission creep, he is looking for a weekend driver that is as close to stock as is cost effective, gotta stay in budget.

If those are original seats I wouldn’t skip that step . I doubt they are steel . You’ll really have some dings if one of those let loose . 

[madkaw]

2 hours ago, Patcon said:

@madkaw

How noisy was the debris in the cylinder?

For a split second on start up . I had been welding dirty steel on my work bench and the head was also on the bench . One of those molten BB’s must have danced right into the port opening . Some more had burned themselves into the side of the port that I found later . That’s how I figured out what happened . It did take a while if scratching my head . What made it more strange was I had a rod bearing go on that engine . They issues were not related 

[madkaw]

1 hour ago, grannyknot said:

There is lots of stuff I'd like to do.😀   The valves are in good shape and so are the guides, also Dave would like to avoid mission creep, he is looking for a weekend driver that is as close to stock as is cost effective, gotta stay in budget.

Might want to check how close those dings are to the fire ring on the HG - they look close