Author Topic: 1988 Turbo 'Vert Project  (Read 1043 times)

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Offline toplessFC3Sman

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Re: 1988 Turbo 'Vert Project
« Reply #165 on: April 24, 2017, 10:15:15 AM »
I've been very hesitant to borrow tools or anything since I really have no idea when I'll be finished - taking care of my son Paul, work on my thesis, the house, and all sorts of things keep getting in the way. Anyhow, I've been slowly chipping away at things like getting the radiator and oil cooler cleaned and pressure-tested, more disassembly and cleaning of individual parts etc. I haven't started cleaning the engine bay yet, but individual parts are coming out ok.

Basically, a giant tub of simple green and water that I let stuff soak in for a few days, then scrub with a wire brush for a little bit, and re-soak if necessary. The two smaller cans are white vinegar, diluted to about 25% to eat away rust on bolts, the front pulleys etc. This has been working well, especially combined with a bit of wire brushing too. Then, all the clean aluminum manifolds, brackets etc in the top tub and box.


Parts storage, after cleaning. Some of the bits have been painted after de-rustifying them, like the water pump, block-off plates and other steel/iron pieces.


Definitely found the source of the coolant leak - these coolant seals were really toast! Both were already broken when I lifted the end iron off the stack, and the inner one had mostly separated into three individual strands. At least this rotor and housing was very clean - yay water injection?






I've been trying to keep everything well-organized through liberal use of trays, boxes, zip-lock baggies etc, to make sure that I know where everything goes back to when it finally comes time for reassembly. So far, all the internals look like they're in good shape, with only a little bit of marking on the end plates where I imagine the rotor sat for a while when the car was parked. No grooves (especially not big enough to catch a fingernail on), and nothing else that looks worrying on the housings or bearing surfaces.



And thats where I had to stop yesterday; about half done. I've had to do a bit of drilling and tapping on various bolts that have broken off in the block, like oil pan studs, one in the front iron for the water pump, etc. I also want to plug the EGR ports and coolant ports into the LIM more securely. No plans for porting - I'm happy with the power potential of the mostly stock porting, and don't want to trade off engine life, idle, or low-load drive-ability for more power at this point. The guy who rebuilt it before said that he did a very mild bit of porting on the exhausts - I don't really see any signs of it, but then again this is the first rotary I've torn down, so I don't have a basis for comparison.
« Last Edit: May 09, 2017, 09:41:17 AM by toplessFC3Sman »

Offline murz

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Re: 1988 Turbo 'Vert Project
« Reply #166 on: April 24, 2017, 03:32:46 PM »
Awesome! Are you buying new hard seals? How do the bearings look?

If you do buy new hard seals, I'd recommend FD corner seals and springs. Should take some pictures!
1986 AS GXL Turbo swapped
1991 BB convertible
1993 VR R1

Offline toplessFC3Sman

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Re: 1988 Turbo 'Vert Project
« Reply #167 on: April 25, 2017, 01:15:22 PM »
I haven't seen anything that would suggest that I need new hard seals, everything looks like its in good shape. I think that the engine already had the FD side seals and springs when it was rebuilt the first time, but I'll take some pics of all the seals just to make sure I'm not missing something. Bearings look great too, but I should get some pics for documentation. I still haven't gotten into the front rotor yet - maybe this weekend.

Offline toplessFC3Sman

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Re: 1988 Turbo 'Vert Project
« Reply #168 on: May 07, 2017, 12:13:21 PM »
Well, I think I spoke a bit too soon in the previous post. Not only did I find a chipped apex seal in the front rotor (fortunately the chip was held in the rotor tip groove)...


... but the bearing in the front rotor looks pretty bad.


Lots of copper showing through, with much of it looking like normal wear, but some sections (especially in that second rotor pic) that look like the babbitt material stuck to the e-shaft of something and got torn off. The E-shaft looks and feels fine, but I'm really not liking that rotor bearing.


Have any of you guys replaced a rotor bearing before? It looks like its just a matter of pressing out the old and in the new, but I know how sensitive bearing tolerances are. Speaking of tolerances, I haven't measured them for the front rotor or any of the other bearings, but I really should.

Also, any preferences for apex seals? I would lean towards OEM since I don't plan on pushing this engine too hard, and would prefer a longer life between rebuilds, but I don't really know what else is out there.
« Last Edit: May 09, 2017, 09:36:43 AM by toplessFC3Sman »

Offline toplessFC3Sman

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Re: 1988 Turbo 'Vert Project
« Reply #169 on: May 08, 2017, 08:44:00 PM »
Just fixed the pictures... google must have changed some of the details of how they host and share photos. Anyhow...

The rear rotor looks fantastic, with no spots where the babbitt has worn through, although there was one line where it was slightly rougher than elsewhere. This may have been from when the car was sitting for about a year between draining all the fluids and getting around to pulling the engine?


There was less than 0.06 mm clearance between the e-shaft and rear rotor bearing (that was the smallest feeler gauge I had), and there was about 0.09 mm of clearance for the front rotor. Too much? The max spec seems to be 0.1 mm, but that's pretty close to the max for an engine that I'd like to get a lot more mileage out of.

All the main bearing surfaces look ok, with some patches of rub-through but nothing that looked too concerning.
« Last Edit: May 09, 2017, 09:35:18 AM by toplessFC3Sman »

Offline toplessFC3Sman

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Re: 1988 Turbo 'Vert Project
« Reply #170 on: September 06, 2017, 11:10:19 PM »
I ended up getting the front rotor bearing pressed out and replaced with a new one since it was looking so beat up. The stationary gear bearings were a little worn but I wasn't as concerned with them. I got new apex seals, corner inserts, and all the o-rings, crush washers etc required to rebuild the engine a while back, so after a long day the weekend after the 4th of July, the engine was reassembled. I didn't take many pictures of this process since I pretty much had my hands full trying to get it done in a day. Spinning the e-shaft by hand, it moved smoothly and gave distinctive compression pulses on all 3 faces of each rotor. The manifold, OMP & lines etc got assembled over the next few weeks, with one stripped hole in the OMP needing to be drilled out and get a threaded insert installed. I found some extra-wide crush washers that would bridge over the threaded insert, and so far it doesn't appear to be leaking.


Everything got a nice cleaning while it was disassembled too... I hope the cleanliness lasts a little while at least. I filled the ports in the intake manifold that used to be used to pass EGR to the intake and coolant to the turbo as well; I've eliminated the EGR system a while ago, and re-routed the coolant to take it out of the manifold so I wouldn't be unnecessarily heating the intake air. This was all filled with a high-temperature putty; i think it was sold for patching exhaust components, but seemed like itd work well for the manifold too. It was like a giant clay stick, but needed to be kneeded to really stick well.


Two weekends ago, I got a day to actually install the engine and hook up the oil & cooling systems.



One of the oil cooler brackets needed a bit of... reinforcement.


Everything seemed to go very smoothly, but the cooling system leaked from a number of places. A few years ago, I had tried to go through and replace a lot of the smaller hoses with bent steel tubing to clean things up and remove failure points, but at the turbo I couldn't find any 10mm compression fittings so I drilled out a few 3/8" tube fittings to fit. They held for a couple years, but didn't survive disassembly well.


This time I ended up buying some 10mm compression fittings and pieces to adapt them to the 3/8" tubing I had from mcmaster.com, and bent/assembled most of the smaller cooling system parts again this past weekend.





Basically, the coolant to the turbo comes out of the nipple on the top of the rear iron pointing upwards, travels under the manifold and out near the firewall, then turns to go through the pipe bolted to the BAC, then back down to the turbo on the passenger's side, and out of the turbo between the turbo and the engine down to the small nipple on the pump inlet.

Offline murz

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Re: 1988 Turbo 'Vert Project
« Reply #171 on: September 07, 2017, 12:49:59 PM »
That's nicely set-up, I ended up bypassing the BAC completely, since it will never really be driven in the winter. That rotor chip could have been really bad, glad it stayed put!
1986 AS GXL Turbo swapped
1991 BB convertible
1993 VR R1

Offline fidelity101

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Re: 1988 Turbo 'Vert Project
« Reply #172 on: September 12, 2017, 11:39:14 AM »
i love mcmastercarr for things like this - excellent solutions on the fly! lol