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Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

I have my oil pan off and want to inspect my engine bearings, I have no noise, no crank backlash or anything just unsatisfactory hot oil pressure, it just doesn't climb with RPM like it should..

By time I got the pan down tonight it was dark so I didn't get to see much, the bottom sides of my pistons look like brand new, and the bottoms of the bores on 1 and 4 look beautiful, thats all I got to see in there so far..

I caught the first of my oil in a big ziploc bag to inspect it, I've had it hanging with a corner low now for hours and there is absolutely nothing in it, nothing..
Nothing bad in the oil pan either, some dark areas in the low spots but no sparkles or anything of that nature other than a coupe 1mm size flakes that look like aluminum but they are not concerning me, I'll hit them with a magnet tomorrow and inspect further.

I'm sure I'll shoot some pics of my dirty oil pan and its insides, crank, bottoms of bores, and stuff for you guys tomorrow

I plan to pull all the bearings and inspect them, I'm thinking I will plastigauge them all but I'm not sure if that is necessary, can I just look at them and if they look copper they are bad or how does that go? I'll just plastigauge them anyway probably..

Could anyone help me with the rundown on the procedure to plastigauge the bearings? I get the basic idea but I want to be sure I'm doing this right..

Take off bearing cap and 1 side of bearing, put strip of plastigauge in (which direction?), torque cap back to spec, remove cap and compare squished plastigauge to paper chart, reinstall cap torqued to spec (if good), repeat X8..

I think I'll just do them all one at a time so I can't mix them up or do anything stupid like knock into them sitting and get them dirty.

I still need to figure out what color plastigauge kit I need for the right tolerances etc and what tolerances I'm looking for..

Any advice?

This seems like something good/fun to do while my car is down for turbo repairs..
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80 Turbo - Slightly Modified

jason c · Joined: 13 Jan 2014 Posts: 1018 Location: Nwi

Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

I'm just trying to chase low hot oil pressure issues, <3 bar at 5k rpm isn't good right?

Something is wrong and I want to catch it before I have to get the crank turned or find another short block..

As far as I can tell so far there is no backlash in any rod bearings from moving the crank back and forth, I need to find the side to side movement tolerances for them too..

No I haven't looked at the haynes yet but I will, I don't really like that thing, last time I used it it tried to get me to set my timing wrong..

I may do something about cleaning out the crank breather while I'm around there too, the hose I replaced off of the AOS was nasty....
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80 Turbo - Slightly Modified

jason c · Joined: 13 Jan 2014 Posts: 1018 Location: Nwi

Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

I'm running 15-50 valvoline (napa label) full synthetic..

I want to plastigauge my cam bearings also..

I'm not burning any oil at all, not loosing any oil, couple drips from my filter adaptor is all, never have to add more oil.

I believe I've had the pressure relief valve out before when I first got the car, what exactly am I supposed to inspect that thing for?

What about the spring and stuff in the filter adaptor? Thats just the thermostat for the cooler correct?

I do get 6-7 bar oil press cold iirc, like summer cold start..
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80 Turbo - Slightly Modified

maybeoneday · Posted: Tue Jul 28, 2015 4:00 pm Post subject:

I would not think 3 bar is totally terrible at 5k rpm I would expect any four cylinder to between 3-5 bar at a hot 5k rpm, dropping down to anywhere as low as 1-0.5 bar at hot idle. I would not be expecting a very major issue here. Check the cam oiler elbow while you are looking for it I cracked mine with a really light nudge, i think they may get brittle (fixed now).
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1977 924 NA Auto

Carrera RSR · Joined: 08 Jan 2010 Posts: 2312 Location: Somerset, UK

I hope you have new con rod bolts ready to fit. Old ones need to be binned once used and removed, more so on a modified turbo motor
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

924RACR · Posted: Tue Jul 28, 2015 10:55 pm Post subject:

MikeJinCO · Posted: Tue Jul 28, 2015 11:07 pm Post subject:

Ideola please start a thread on that, I'd be in.
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Mike

'67 MG Midget Dp
'71 Ocelot Dsr Kawasaki 1000(under rebuild)

Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

ideola · Joined: 01 Oct 2004 Posts: 15550 Location: Spring Lake MI

I might just have a cam and set of lifters...let me look into it and get back to you.

As for the rod bolts....

Regarding Vaughan's race engine, keep in mind, I believe he typically tears that engine down at least once per season, so the bolts are being rechecked periodically.

The OEM design are stretch bolts and are intended to be replaced, not reused. People have reused them out of necessity, some with success, and some with failure. YMMV. Unfortunately, there are no OEM replacements available, so the only option we've had for some time now are the ARP replacements we commissioned a few years back.

I think we've done 3 or 4 group buys on those now, which is the only way to get them. Minimum order is 80 pieces (10 full sets of

. I'm presently not in a position to underwrite a group buy, as I did the last time around, so we would need a solid 10 commitments to order. I'll get a thread going in the next day or so.
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erstwhile owner of just about every 924 variant ever made

924RACR · Posted: Wed Jul 29, 2015 2:55 am Post subject:

Well, my race motor is not boosted, and we don't rev the piss out of it; normal usage, we shift at 6k.

The rod bolts and nuts... are original. Sorry.

Didn't have ARP as an option, way back when I built the motor.

The street 931, OTOH, does rock ARP bolts and head studs, after a rebuild necessitated by a snapped stock original rod bolt.

The race motor is also not heavily modified, makes maybe 135-140 crank hp.

As for my feedback - I've been extremely busy with trips to the 'Ring, and working on my other racecar in the meantime, so haven't had much time to play on the board. Sorry. But your effort is not wasted.
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

Fasteddie313 · Joined: 29 Sep 2013 Posts: 2595 Location: MI

Quote from EBS for there parts prices..

Bearing prices aren't too bad..

Con rod nuts $9 a piece? Get outta town..
OEM head studs $1.85 each all day, great price..
Awesome price on complete head gasket set, that comes with valve cover and exhaust gaskets etc too.. Best price on a HG period?
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80 Turbo - Slightly Modified