Engine Swap or Rebuild?

[corbenB]

Hi, first time poster here, I found copper flakes in my oil last week, despite having no rod knock. Car seemed to be running fine when I did the oil change. I was wondering if because I found out my bearing was going bad before it had "spun", should I try and attempt to just replace the bearing, whether it was main or rod, and move on? or should I just be looking for a new engine entirely. I took it to a shop for them to look it, and they quoted me at like 6500 at the high-end for repairs. I'm assuming that that's if the damage is extremely bad and pistons/block need to be resurfaced? I don't know where to go from here, so any advice is welcome. Thank you!

[Zed Head]

What engine?  How many miles?  What do you know about it?  

Can you post a picture of the copper flakes? Might just be from the washer on the drain plug.

[Reptoid Overlords]

$6500 will get you a Datsun Spirit stage 2 engine. 

[Mark Maras]

 I'd mic the crankshaft journals and the cylinder walls before making a decision. 

[corbenB]

1 hour ago, Zed Head said:

What engine?  How many miles?  What do you know about it?  

Can you post a picture of the copper flakes? Might just be from the washer on the drain plug.

Car has a N42 Fuel injected L28 with around 136000 miles on it. It was the previous owners first car in highschool, and he bought it from some guy in nevada. I'm assuming he kinda beated on it in HS because there was a lot of shitty electrical work done to it when I got it. Car had some tick but I know these are pretty noisy engines so i never really worried about it too much.

[siteunseen]

Could be rotting radiator or some type radiator repair flakes.

I'd flush all the coolant out from the block up and through the radiator. Then change oil and filter with cheap Walmart oil and see what comes out after a little driving.

Looks like a rotten radiator to me.

Edited January 13, 2022 by siteunseen

[Patcon]

What kind of mechanical skills do you have?

An engine rebuild is really not that hard if you have the right reference materials

[Zed Head]

Looks like the silver foil from the top of a gallon jug of oil.  ?

If it is a bearing failing you will hear it eventually.  Measuring cylinder pressures, examining cam lobes, checking timing chain wear...those are the typical things you'd do to determine engine wear.  136,000 miles is not a huge number for these engines.

 

[heyitsrama]

L-series motors are a great motor to learn how to rebuild, they are stout, parts are relatively easy to figure out, most of the hard stuff is already figured out.

For $6500 you should probably find a new shop. You can probably do a stock rebuild for sub-$1k if you DIY. If you choose to go down that route, perform a leakdown test (or compression if you cant get access to a leakdown) and take notes of what the values are, it will give you insight to engine wear.

[Dave WM]

if the engine is running well, no odd noises, compression checks out, oil pressure good, not burning excessive oil (a quart is less than 600 miles is considered excessive), head gasket ok (check for exhaust gases in radiator with simple test kit that looks for a color change in a fluid, sold at napa), oil does not seem to have water in it (milking looking). then I would just  change the oil and drive it, see if those bits show up again at the next oil change. I generally do an oil change ever 3k miles, after adding 2 qts during that time (I burn about 1q per 1000 miles). That's using valvoline 20/50 racing oil in the summer and 15/40 rotella T4 in the winter. Its pretty hot where I drive so I use the high side of the recommended range of weights.

Edited January 14, 2022 by Dave WM

[siteunseen]

15 hours ago, Zed Head said:

Looks like the silver foil from the top of a gallon jug of oil.  ?

If it is a bearing failing you will hear it eventually.  Measuring cylinder pressures, examining cam lobes, checking timing chain wear...those are the typical things you'd do to determine engine wear.  136,000 miles is not a huge number for these engines.

 

You're right Zed Head, it does look like foil and my comments on the radiator were knee jerk reaction after seeing them. The radiator doesn't mix with the motor oil. Sorry

I wonder if the front crank gear could cause those brass looking slivers?

[corbenB]

On 1/14/2022 at 5:13 AM, Dave WM said:

if the engine is running well, no odd noises, compression checks out, oil pressure good, not burning excessive oil (a quart is less than 600 miles is considered excessive), head gasket ok (check for exhaust gases in radiator with simple test kit that looks for a color change in a fluid, sold at napa), oil does not seem to have water in it (milking looking). then I would just  change the oil and drive it, see if those bits show up again at the next oil change. I generally do an oil change ever 3k miles, after adding 2 qts during that time (I burn about 1q per 1000 miles). That's using valvoline 20/50 racing oil in the summer and 15/40 rotella T4 in the winter. Its pretty hot where I drive so I use the high side of the recommended range of weights.

Honestly I don't really burn any oil, it may be cause i don't hit highway speeds often or anything, but i've never checked my dipstick and it said anything below full. But yea this is my current plan, it doesn't have any misfiring but I'm still planning on doing a compression test. My reasoning for not changing the oil was that I hadn't hit 3000 miles on the cycle yet, but it had been sitting on and off for a year cause I had a series of electrical issues. But thank all you guys for your advice.