89 951 engine overhaul

[Tom]

I waffle between building the big 3 liter I have prepped, or redoing the original 2.5 and using a cheater turbo like this for a bone stock look.... In the meantime, absolutely get a blast cabinet. They are incredibly useful. If you get the cheap HF version, see YouTube for a handful of modification that make it dramatically more effective, including in particular better lights and a gravity feed at the bottom rather than the suction tube feed they come with.... That vacuum on the side is for the higher-end HF cabinet, but I was able to adapt it with (of course) a 3D printed flange.

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[chris white]

I ordered some [rods]... and the 0.5mm oversize Mahle pistons linked in earlier.

Info on the LN Engineering site says the Mahle pistons are only intended for use with Alusil, but Millennium Tech says customers use them all the time with Nikasil. So, is the piston coating compatible with Nikasil but the rings are not, so if using with Nikasil one just needs to change the rings? Would be good to know for sure if anyone has information... paging Chris White

the coating is not a serious problem, in a prefect world I would bead blast is off the pistons. The rings are the real issue. general rule - hard cylinder wall uses soft rings and soft cylinder wall uses hard rings. Typical Alusil rings have a chrome finish and that will never seat on a nikasil wall.

On blasting cabinets - the better ones are worth it! you don't have to get the dedicated vacuum - a shop vac works fine. Never ever ever glass bead blast a cylinder head or intake manifold. You can't get all the glass beads out....years later one will fall out every now and then. One glass bead will destroy your cylinder walls. I have a second cabinet for baking soda blasting.

[four0four]

Picked up some odds and ends from HF, including the blaster cabinet. Forgot the media - d'oh.

I wasn't gonna touch the head, but you probably saved the intake. Is there any reason not to use the same cabinet with different media?

Otherwise...Finally got the oil pump apart, and well. Might get a new-to-me-one:

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I think I've mentioned before the car had some kinda front end damage (in the 90s!). Externally looks fine, but the radiator bracketing is off true. There's some nice looking bosses I was planning on mounting an oil cooler to, but now if I'm to do so I need to square them up first. Would've helped if I'd taken pictures, but I was too busy being annoyed!

[chris white]

Just put a wire wheel on your drill and clean the intake that way. It actually brings out a nice finish. One of the problems with grass bead blasting is that it leaves a finish with ‘tooth’ (texture) that grabs ahold of dirt. The wire brush technique is also great because you can touch it up anytime.

[four0four]

I've got one for the grinder - I'll find one I can use for the inside too. Is there any benefit to grinding off the casting flashing?

Likewise: Would soda be a viable media here? I've really no idea what I'm doing when it comes to blasting

[chris white]

Soda blasting is great for cleaning engine parts since it’s water (or solvent) soluble - easy to clean off the residue. But it also takes a lot longer and if it sits in humidity for any length of time the baking soda will clump up and stick together.
So - the question is are you cleaning for looks or for building? I use bead blasting for external brackets, valves (when out of heads), piston tops ( although I rarely reuse pistons), connecting rods. I use soda for heads and blocks and for just about everything else I use a wire wheel - even the parts that get bead blasted get hit with the wire wheel. I like the look and it doesn’t attract dirt or oil.
Anything with casting texture that is exposed to the interior of the engine does not go in the bead blast cabinet- too hard to get all the beads out!!

[chris white]

Go to Amazon - you can buy wire wheels to chuck in you cordless drill by the dozens. 3” minimum, get a number of sizes

[Tom]

Check out the Tacoma Comany on Amazon for blast media. When I switched over from HF media to this stuff, I was kicking myself for using HF stuff for so long. The HF glass bead isn't very beady, and is like a dust bomb that makes it hard to see what you're doing. Also, be sure to check out all the various mods people make to the HF cabinet. As designed, they are very Harbor Freighty but with the right mods they become way better to use. The gravity feed set up is the biggest thing (a must) plus better lights, gun, dust collection, sealing the cabinet, sacrificial glass protection (Lowes has a piece of glass they will cut that makes 3 replacements), rolling cart, and as much shop air as you can muster (even linking multiple compressors if needed). There are literally hundreds of YouTube videos on the topic...

[four0four]

Thanks guys

Wire wheels on order, HF cabinet is sitting in the garage with a handful of modifications (sealants, air regulator/dryer). It'll take another weekend before it's ready.

So - the question is are you cleaning for looks or for building?

Building primarily, but things need to be clean enough to track down leaks and such. Which they weren't.



Any wisdom on that oil pump? it's less clear than I'd like in that picture, but there's a bit of a gouge around the outer race...I don't know if it'd be better to try and clean it up, or gamble on ebay

[four0four]

Still alive out here - Been dragging my feet assembling the blast cabinet (though I've got a cool printed dust funnel I can't wait to try)! Eyeballed and welded up the WBO2 bung while I had the stuff out from pulling the clutch fork:

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Judge me not too harshly - It's a janky TIG setup built on a stick box. At least I got backpurge working!


Otherwise, ordering another oil pump housing and...still...trying to get C&D to give me a date. Casually poking around for alternatives but not super optimistic. A one-shot job must be small fry in this day & area...


Edit: Oh! And I figured out my oil cooler plans - just for now going with a 2nd stock one, mounted mirrored to and in series with the original. Happily, Setrab's 22mm to AN-12 fittings are a perfect fit