Having some issues on a fresh build

KicknAsphlt

KicknAsphlt

Occasional Peruser
Nov 20, 2005
581
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Denver, Colorado, United States
www.jkbweb.net
Hey guys, finally got the car started yesterday, but ran into some issues that I'm still trying to puzzle out. I guess I'll go by bullet-points to keep things organized.

- Not registering any vacuum signal on vac/boost gauge, and AFPR pressure doesn't change when disconnecting vac line

- Gauge on AFPR and my gauge inside the car (sender is on the fuel rail) read different pressure readings; 33ish on the AFPR gauge, and about 10psi higher on the fuel rail gauge.

- Oil pressure on guage doesn't come up much above 20psi; I did the pump shim mod when I built the motor, and installed a temp-controlled oil cooler setup. Couple things I noticed -- it looks like the block-off plate below the block adapter is seeping oil, as well as the oil filter on the remote mount. I did polish up that gasket surface when I bought it so that it was nice and smooth. I'm wondering if the pump is producing the pressure, but maybe my oil cooler is the restriction? It's the factory oil cooler from a gen-2 RX7; I was thinking of bypassing the cooler to see if that's the issue.

- Still have some coolant leaking...took care of the big ones I missed so far. I think it's seeping either from the thermostat housing or the coupler that fits onto it from the upper radiator hose (have the aftermarket hardpipe installed). One thing I did notice is that the top of the radiator gets hot, but the bottom is staying cold/luke-warm The radiator is a Fluidyne, I bought it BNIB from another member on here about 5yrs ago...never been used, rad cap and port caps remained on until I hooked the hoses to it. Another thing I noticed is that on the couple times I've taken it out, the car heats up quick when putting a load on it, but it'll cool down pretty quick when not.

- Finally, not a big issue, but the ABS light is on. I did have a code 31 last night, but after reseating the connector on the AFM it seems to have disappeared for now.


I guess the thing I'm afraid of most is that I screwed something up when putting this motor together....or that with it sitting so long, things might've degraded or something happened to it. Car was sitting outside during colorado summers and winters until a couple months ago, and I dropped the assembled motor back in about fall of '09. Exposed oil ports were covered (turbo drain and crankcase vent), but there were no spark plugs in the head. If any of you guys have ideas on where to start with these issues, I'd really appreciate the assistance....not really sure where to begin here. :1zhelp:
 
J

jake8790

Life's too short for N/A
Dec 18, 2011
395
0
0
Oregon
-vacuum hoses directly to intake manifold?
-oil pressure should be higher than 20 when driving. Fix the leaks. Try bypassing the cooler. Did you replace the oil squirters when you rebuilt the engine?
-Hot at the top, cold at the bottom means the radiator is cooling properly. Temp should stay steady though. Try a new thermostat.
-Sitting outside for years with no spark plugs was a bad idea.
 
KicknAsphlt

KicknAsphlt

Occasional Peruser
Nov 20, 2005
581
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18
Denver, Colorado, United States
www.jkbweb.net
No, I didn't replace the oil squirters when I rebuilt the block...though in hindsight, I probably should've. Admittedly, I was in the mentality of get it back on the road with a running motor, then I was going to build up my original block later down the road, so this block wasn't intended to be a long-term replacement. I am going to pick up the fitting I need tomorrow thought to bypass the oil cooler, and I did buy a mechanical gauge that I'm going to thread into the port where the factory sender normally goes. As for coolant leak, I'm pretty sure it's the T-stat housing, so that'll get fixed tomorrow as well...probably replace the T-stat as well while I'm in there.

I made some headway with the vacuum issue tonight though -- I think I need to repair the nylon line for my boost gauge, and also the vacuum manifold wasn't getting engine vacuum because the feed line I was using was too small (WHOOPS!)...was using the small fitting on the back of the intake; now I've spliced in from the line that feeds the brake booster and the vacuum manifold has full engine vacuum now. I was also able to verify that the engine at idle is pulling 12-13" of vacuum (12 if going by the autometer, 13 if going by the U.S. General (Harbor Freight) gauge I cannibalized from a broken hand vacuum pump).

Hopefully I can get the coolant and oil issues resolved tomorrow, and I'm hoping that this 20psi oil pressure thing is just a fluke....I'd hate to have to pull the motor all over again without really getting to break it in. Thanks again for the suggestions so far, any others please chime in. I'll report back tomorrow with a verdict on the oiling and coolant issues.
 
KicknAsphlt

KicknAsphlt

Occasional Peruser
Nov 20, 2005
581
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Denver, Colorado, United States
www.jkbweb.net
Update:

Thought I had the leak nailed to a coupler on the upper radiator hardpipe that had a torn inner wall. Just found out about an hour ago that it's still leaking, looks like the T-stat housing for sure.

As for the oil pressure issues, that's where the fun REALLY begins -- Hooked up the manual gauge from HF and fired it up; gauge would start at about 22-23psi at idle and would actually DROP pressure when I gave it some throttle. So, I took the gauge kit back to HF and exchanged it, thinking it might be a faulty gauge...we all know the quality there...lol. At any rate, come back with my new kit, hook up the gauge, start the car......SHIT....same thing. So while I'm in a pissy mood and about ready to take a match to the car, I decide to try bypassing the rx7 oil cooler before I break out the matches. Start the car again after hooking up the feed and return lines to a union fitting, start the car.....

HOLY SHIT, have a good ~55psi on the gauge! Give it some gas, and it jumps to about 60. So, looks like the culprit was the oil cooler, which is what I was hoping/suspected (hoping because it would be the simplest to fix, suspected because it was the only unknown-condition used part in the oiling system...everything else was either brand new or I got from trusted sources).

So, all I need to do is fix the coolant leak from the t-stat housing and I should be set. My main question now is, since I have to take it somewhat easy on the motor for the first thousand miles or so, will I be ok running with the oil cooler bypassed for a while? I plan on having a new setup long before that 1k miles is reached, but I'd like to be able to get the break-in run done and start driving this puppy. Plus, I've only got a week-long temp registration before I have to go get the car smogged and fully-registered. Inputs? I know keeping the oil fairly cool is important on a boosted vehicle, but aren't there a lot of boosted vehicles that don't have an oil cooler? Please weigh-in, I'd love to hear everyone's inputs.
 
KicknAsphlt

KicknAsphlt

Occasional Peruser
Nov 20, 2005
581
1
18
Denver, Colorado, United States
www.jkbweb.net
Update:

Fixed the coolant leak on the T-stat housing...looked like the hose below it was leaking as well; tightened the clamp more and seems to be ok. After that, I tried burping the system -- One thing I noticed was that even after the engine came up to temp, the lower rad hose was still cold while the upper hard pipe, top rad tank, etc. were hot. I know cooler lower hose is how the system is supposed to work, but this was with the e-fans off and no air blowing across the radiator, so I would think there would be some sort of heat-soak going on there. If you watch the video, my main question is, is that normal??? I've burped the system on my truck a few times before and I've never seen anything like that. Also, one thing I noticed was that when I gave it a little throttle to up the RPMs, the turbulence went away, but came back again after it went back down to idle.

[video=youtube;grr2ZvgNvA0]http://www.youtube.com/watch?v=grr2ZvgNvA0[/video]


After I turned the car off and was topping up the radiator again (had a nice little fountain out of the water neck when I shut the car off), I noticed some weird floating stuff in the coolant.

[video=youtube;B988WQS3LGU]http://www.youtube.com/watch?v=B988WQS3LGU[/video]

[video=youtube;w0AfthlHXUM]http://www.youtube.com/watch?v=w0AfthlHXUM[/video]


I'm kind of stumped on this coolant issue, and I don't want to take forever trying to keep burping the system or chasing down a pressure/flow issue...I feel like my window for seating the rings is closing fast (if it hasn't closed already), and the last thing I want to do is yank the motor again and replace the piston rings on a fresh build...
 
KicknAsphlt

KicknAsphlt

Occasional Peruser
Nov 20, 2005
581
1
18
Denver, Colorado, United States
www.jkbweb.net
KicknAsphlt;1831165 said:
Update:

Fixed the coolant leak on the T-stat housing...looked like the hose below it was leaking as well; tightened the clamp more and seems to be ok. After that, I tried burping the system -- One thing I noticed was that even after the engine came up to temp, the lower rad hose was still cold while the upper hard pipe, top rad tank, etc. were hot. I know cooler lower hose is how the system is supposed to work, but this was with the e-fans off and no air blowing across the radiator, so I would think there would be some sort of heat-soak going on there. If you watch the video, my main question is, is that normal??? I've burped the system on my truck a few times before and I've never seen anything like that. Also, one thing I noticed was that when I gave it a little throttle to up the RPMs, the turbulence went away, but came back again after it went back down to idle.

[video=youtube;grr2ZvgNvA0]http://www.youtube.com/watch?v=grr2ZvgNvA0[/video]


After I turned the car off and was topping up the radiator again (had a nice little fountain out of the water neck when I shut the car off), I noticed some weird floating stuff in the coolant.

[video=youtube;B988WQS3LGU]http://www.youtube.com/watch?v=B988WQS3LGU[/video]

[video=youtube;w0AfthlHXUM]http://www.youtube.com/watch?v=w0AfthlHXUM[/video]


I'm kind of stumped on this coolant issue, and I don't want to take forever trying to keep burping the system or chasing down a pressure/flow issue...I feel like my window for seating the rings is closing fast (if it hasn't closed already), and the last thing I want to do is yank the motor again and replace the piston rings on a fresh build...
Click to expand...


Bump....anyone? Bueller...?
 
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