Jump to content

IGNORED

1983 280zx turbo engine


Recommended Posts

Posted (edited)

thought I would start a fresh thread to document my journey on getting a turbo engine to run and perhaps install in my 1975. I say perhaps since at this point my main interest is to learn about turbos, and if I like what I learn I may install but will make sure its reversible since my car is an excellent example of a survivor. So now that all the qualifiers have been stated...

as titled its a 1983 i assume based on the P90a head with the hyd lifters. So far all I have done is mount the engine on a test run stand that and I have attached manifolds and EFI for NA testing. I will be swapping out the dizzy drive to use the standard dizzy since that is what i have used on the last NA engine that I had on the stand. The plan is to eventually run the stock turbo and turbo EFI, but for now I just want to get some NA base line runs.

The engine is extremely dirty with carbon both all over the valve train and in the pan. I cleaned out the pan and picked out the large carbon chunks from the top of the head under the cam.

I have started to clean the lifters, found an excellent video on youtube as guide. Its very satisfying so I will finish up that before test firing the engine.

I have a new oil filter and oil (15-40 rotella T4) for the initial test. I spun the engine on my test stand to confirm oil, At 1st there was no pressure so I pulled the pump and filled it, after that the oil pressure came up fine. I had one cam oil hole not producing any dribble so I poked it with a fine wire, and cleared. 

Based on the overall dirtiness I can see I will at the very least need to pull the cam, and flush with brake clean and prob use a gun bore brush to clean it, or else risk re fouling the oil feed holes in the cam.

The head had an excellent leak down test, the compression test on the stand was 2-6 all about 150 psi, 1 was 125. I am not sure if my starter was just getting weak at that point so I will test again after running. I have seen this before with engines that were left sitting for long times in storage, so not too worried about it at this time.

during the NA test run phase I plan to  check for exhaust gases in the coolant and coolant in the oil, standard stuff to see if the block/head are ok. 

If all those test check out the next step will be to remove the engine for a complete tear down and assessment of things like bore condition, bearing wear, rings etc...

Based on the condition of the oil I would expect to find some pretty dirty rings.

I have had the stock turbo rebuilt by a local shop. It looks GREAT will post up some pics later. The turbo was really trashed, and the oil supply as the culprit. The oil line is really filthy so before any turbo runs I will need to get the engine block hot tanked, the oil gallery plugs removed and clean out any junk in the galleries. The turbo is just too nice to even consider bolting on until I am sure it will have  a clean supply of oil. 

I have some early video on my channel of just mounting up the engine to the stand if you would like to see. they are on my youtube channel 

stay tuned as I progress. I will need some help on ideas about getting a clean oil supply line as the old one is I think beyond cleaning. Its on the back burner since so much else has to happen before the turbo as mentioned above but I would like to start planning. 

 

 

 

 

 

 

 

 

 

Edited by Dave WM
  • Like 3
Link to comment
Share on other sites

progress so far..

removed the cam shaft, took it to a shop where they polished it. It had some pretty bad scoring on #10 and #9 cam base circle. for some reason the damage seemed limited to just the base and not the lobe itself. But since it had hyd pivots the base stays in contact so I did not want to run it and do more damage. the rockers themselves looked ok. The shop said it really should be re ground to clean it up, but agreed to try a polish. He said it came out better than he expected. I will take that as a partial win.

The cam bearing surfaces looked good both on the camshaft and the towers. there was some burnt oil on one side of the tower bearing I cleaned it up with some carb cleaner. Again the engine looks to have had too few oil changes, hence the cleaning of parts as I go.

the pivots are tedious but strangely satisfying. I to the tear down, drain the old oil, soak in gas, remove the internals, spray off with brake clean, allow to dry, then dunk in the gallon sized carb cleaner  (the one with the basket inside), let it soak for about 30 min, comes out pretty clean, use some Q tips and simple green on it. If its still dirty it gets dunked again. I am not sure if you can damage anything by leaving it too long, prob should do some research on that.

Anyway when clean I reassemble in a oil bath to keep air out, then clean out the head well of oil where they screw in, and tighten to about 62 ft lbs.

  • Like 2
Link to comment
Share on other sites

re installed the cam shaft. I wrapped the lobes with some electrical tape making sure to cover the edges. I found it MUCH less stressful doing the install since I did not have to worry so much about the sharp edges of the lobe contacting the bearing surfaces. 

Link to comment
Share on other sites

ok got it started on the test stand today. Bad news I get a lot of oily brown foam coming out of the rad (I left the cap off so I could monitor the coolant level).  Pretty sure the oil level in the crankcase dropped as well. had some but not a lot of exhaust gas in the rad as well after testing with the blue turn yellow test kit (it was just a slight green actually). I retested the compression all were right at 150 psi, and did well on the leak down test (most were 90% one was about 85%).

temps went up not crazy high but def higher than should be, on the other test engine it was rock solid at middle of th e gauge this one was more like 2/3 towards high.

Oil pressure seemed lower on this engine as well. I was thinking it was just the higher temps thinning out the oil.

so based on the brown oily foam, apparent loss of oil in crankcase, and elevated temps I am HOPING its a blown head gasket. the Compression test don't really show that, but i would much rather have a head gasket problem over a block or head problem. I will get some video of it tomorrow to share, perhaps someone else will recognize if I show vid

I am pretty sure my next course of action will be to pull the head. 

Oh and I love the hyd rocker pivots. NO valve clatter at all. 

Link to comment
Share on other sites

  • 2 weeks later...

some progress beside what I started on the P90a head..

Pulled the next to last main bearing, very little wear, two tiny scratches (on the bearing the journal looks perfect). the two scratches are hair thin, I am going to leave them be IF test with plastigauge are ok.

Pulled #2 conrod bearing again virtually no wear, and journal looks perfect. This engine looks like a low mileage low oil change or maybe cheap arse oil used. everything on the outside is coked up, the turbo was thrashed but the bearing and the cylinder hone looks low mileage. 

I was thinking of removing # 2 piston while the rod bearing was apart to inspect the rings, mainly the oil control rings (the leak down test shows good compression). 

This is new territory for me, (never tore into an engine before, I am an electronics guy not a mechanic guy). so each thing i do is new. I was thinking if the oil control rings are gummed up with the same cheap arse burnt up oil, maybe I could dunk the piston in my berrymans parts cleaner can and soak them. Clean off and reoil then reinstall. Thinking on it while waiting on the dumb plastigage, AZ showed in stock at local store but guy could not find it. 

 

 

 

 

 

  • Like 1
Link to comment
Share on other sites

Melted chocolate ice cream=bad head gasket oil leaking into coolant. There are 2 pressurized oil ports from the block to the head and they have restriction orifice in each. I have circled them in red. Whenever I do a head gasket I use Locktite 515 light coating on the metal reinforced holes I have circled. 515 is Anaerobic (only dried when no oxygen is present).

https://www.grainger.com/product/5E226?ef_id=CjwKCAjwwo-WBhAMEiwAV4dybTZyPbY-H5icKkwUzaiPmBp0NjntWAzyiw674kgkAxdh8noJCgWmJBoCWD4QAvD_BwE:G:s&s_kwcid=AL!2966!3!496359974779!!!g!1635640739665!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=CjwKCAjwwo-WBhAMEiwAV4dybTZyPbY-H5icKkwUzaiPmBp0NjntWAzyiw674kgkAxdh8noJCgWmJBoCWD4QAvD_BwE&gclsrc=aw.ds

There are lots of arguments about using gasket sealant on head gaskets for the L28 engine. That's a decision that is up to you. I grew up using aircraft sealant (Permatex Aviation Form-A-Gasket on my head gaskets but most of the engines I did in my early years were cast iron blocks and cast iron heads.   https://www.westmarine.com/permatex-aviation-form-a-gasket-sealant-4oz-13630512.html )  I chose not use sealant (except the red circles) on my 81 N/A and my 83 N/A in the last 2 years. That was my choice. 

I did go back and re-torque the head bolts when the engine was warm after taking the car on a couple of break-in runs.

Gasket.jpg

Link to comment
Share on other sites

5 hours ago, Dave WM said:

I am an electronics guy not a mechanic guy.

I thought you were a numbers guy, not an electronics guy?

I mean... Seeing your place, one would never guess that, but isn't that the case?    LOL 

  • Haha 1
Link to comment
Share on other sites

9 hours ago, kickstand80 said:

Melted chocolate ice cream=bad head gasket oil leaking into coolant. There are 2 pressurized oil ports from the block to the head and they have restriction orifice in each. I have circled them in red. Whenever I do a head gasket I use Locktite 515 light coating on the metal reinforced holes I have circled. 515 is Anaerobic (only dried when no oxygen is present).

https://www.grainger.com/product/5E226?ef_id=CjwKCAjwwo-WBhAMEiwAV4dybTZyPbY-H5icKkwUzaiPmBp0NjntWAzyiw674kgkAxdh8noJCgWmJBoCWD4QAvD_BwE:G:s&s_kwcid=AL!2966!3!496359974779!!!g!1635640739665!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=CjwKCAjwwo-WBhAMEiwAV4dybTZyPbY-H5icKkwUzaiPmBp0NjntWAzyiw674kgkAxdh8noJCgWmJBoCWD4QAvD_BwE&gclsrc=aw.ds

There are lots of arguments about using gasket sealant on head gaskets for the L28 engine. That's a decision that is up to you. I grew up using aircraft sealant (Permatex Aviation Form-A-Gasket on my head gaskets but most of the engines I did in my early years were cast iron blocks and cast iron heads.   https://www.westmarine.com/permatex-aviation-form-a-gasket-sealant-4oz-13630512.html )  I chose not use sealant (except the red circles) on my 81 N/A and my 83 N/A in the last 2 years. That was my choice. 

I did go back and re-torque the head bolts when the engine was warm after taking the car on a couple of break-in runs.

Gasket.jpg

thanks for the tip!! I like the idea of the anaerobic on the copper gasket to head and block junction.

Link to comment
Share on other sites

3 hours ago, Dave WM said:

counting beans was just a way to afford real passions

Haha! If you're anywhere near as good at counting the beans as you are with the stuff that you really enjoy, then you must be pretty good at all of it!

I'm not worried at about you opening up your first motor.    :beer:

  • Like 2
Link to comment
Share on other sites

checked on main .0015 (best I could read the plastigage), con rod .001 so looks good there.

pulled one piston (the one I was checking the con rod) rings were nice a loose in the lands pistons looked very good, and no coked up oil in the expansion ring was noted.

Lastly I fabed up a tool for installing the core plugs. Having not done this before I decided I needed a tool to make sure I get the plugs in a consistent correct depth.

here is a short video of the tool

 

  • Like 1
Link to comment
Share on other sites

Your plug installer tool looks great. I spent way too much time making a custom application device on the lathe. Don't have any pics, but when I use it, I'll snap some.

Yours not only took a lot less time to create than mine, but it's also adjustable which mine is not.  Forest through the trees....

  • Haha 1
Link to comment
Share on other sites

Posted (edited)

got head on last nite, TC too, hand spun it all were about 75 psi. Spent a ton of time cleaning the gasket off the engine for the front cover. Will work on the front cover side next. Will prob pop for a dizzy drive just so i dont have to keep swapping them out to run my test stand dizzy. Got some OE core plugs on the way (thanks Jeff, I needed that, anyone remember the old aftershave comercial?).

Edited by Dave WM
  • Like 1
Link to comment
Share on other sites

hope to get the new oil pump spindle today tired of swapping it so I can run a NA dizzy. when I get that in I will be able to button up engine, then I can do another flush thru the open expansion plug holes. the OE plugs should be here monday (not gonna use the made in China dormans 🙂 ).

after I get the the plugs in I am thinking of filling up with some evap o rust and letting is set for a day to get more of the rust out. will just install some rad hose  on the water inlet and fill till it come out the T stat housing. 

oh and got a new OE turbo oil tube on the way from japan, hope it survives the trip. 

  • Like 1
Link to comment
Share on other sites

Posted (edited)

So I hope you actually counted the number of freeze plugs you needed and didn't simply rely on my memory.

Because... Last time we were talking about those plugs in this thread:
https://www.classiczcars.com/forums/topic/67591-p90a-head-f54-block-correct-head-gasket/

I had the numbers wrong... I have since found my bags of plugs and took a fresh look at the F54 block, and here are the correct numbers:

The F54 block has a total of eleven freeze plugs:

Nine 35 mm
One 40 mm
One 50 mm

I bought (a quantity of two) Sealed Power part number 381-8027 sets off rockauto Jan 2020

Each set contains 1-50mm, 1-40mm & 7-35mm plugs and because of that, I had to buy two sets to get enough of the 35mm plugs.

Edited by Captain Obvious
Link to comment
Share on other sites

And about your block rust:
P1160264.JPG

I've got the nipple on the side turned slightly downward to facilitate draining after the evap-o-rust had time to work. And you can see the piece of wire fashioned into a hook to hold the hose up until I'm ready to drain.

Don't shake the shop!! Filled to the brim:
P1160265.JPG

I didn't take any pics of the water pump hole cover at the front, but it's bolted to the block to cover that hole that leads to the front cover. Doesn't have to be fancy. Just something to keep the liquid from leaking out that hole.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy and Guidelines. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.