CRXFi Build Thread (Geo Metro XFi drivetrain in Honda CRX) - Page 14 - Fuel Economy, Hypermiling, EcoModding News and Forum

Christ · 05-20-2010, 11:21 PM

Retorque the head bolts after first warm up cycle, and I like to check them again after about 10-15 cycles, as well, after you've put a few miles on it in varying conditions.

Compression test you can do at any time, really. If you keep a really close eye on it (I mean check it 100 times in the next 30 days or so, then keep an eye on it once a month after that) you'll notice that it peaks out, then drops off a little for each cylinder. The slight drop in compression means the rings are seated and worn in fully. (This won't happen if you used sealed/gapless rings, at least not as noticeably).

Doesn't really matter, I doubt you'll want to keep that close of a watch on it.

After it cools down, drain some of the oil out of the pan and check for metal shavings. If they're there (more than likely are) you can either just change it, or drain and filter it, then put it back in. I often find myself putting the same oil back in and using a cheesecloth or gauze to filter it first, then changing it after 500 miles or a few hours of run time (depending on the application).

blownb310 · 05-20-2010, 11:26 PM

Quote:

Originally Posted by Wonderboy

Thanks for the advice, gentlemen. Much appreciated, and fast! When will it be time to re-torque the head bolts? When will it be time for a compression test? I should really get the temperature gauge working...

Modern head gaskets don't need to be retorqued. A compression test can be done any time you think you have a problem, but if a newly rebuilt engine runs well, I don't see a reason to check it.

Quote:

Originally Posted by Wonderboy

I should really get the temperature gauge working...

Affirmative!

Wonderboy · 05-21-2010, 12:07 PM

I'm going to wire up the temp gauge and tachometer, bleed the brakes, and hopefully take the CRXFi's maiden voayge to the junkyard where I will get some more cosmetic stuff I need for it. There will probably be more updates later tonight when I break my welds on the pass. side axle sheath, or vibrate that hub bearing into smithereens from the axle not being perfectly true anymore

TomO · 05-21-2010, 02:04 PM

Ooh, a little carnage once in a while is fun! Good Luck on your maiden voyage!

Christ · 05-21-2010, 03:08 PM

Quote:

Originally Posted by Wonderboy

I'm going to wire up the temp gauge and tachometer, bleed the brakes, and hopefully take the CRXFi's maiden voayge to the junkyard where I will get some more cosmetic stuff I need for it. There will probably be more updates later tonight when I break my welds on the pass. side axle sheath, or vibrate that hub bearing into smithereens from the axle not being perfectly true anymore

Pick A Part had two Rex sitting in the yard, but they were both fairly gutted. One had a decent cargo set, the other had a fairly decent body on it.

(For anyone not familiar, the "cargo set" mentioned is the pair of pop-open storage boxes to the extreme sides, as well as the lockable storage which all occupy the back seat area of the USDM (and some foreign) CRX models.)

If your lock box has a beat up lid on it at all, it's not hard to rebuild them with either a piece of lauan (very thin wall veneer) or even 1/8" fiber board or plywood, even coroplast would work, really. All the hardware screws through the paperboard backer, so it's all pretty easy to xfer/line up.

Unfortunately, I don't have a good one anymore. I used to have a couple, but when they tag for up to $200 each, you tend to sell things like that quickly.

Wonderboy · 05-21-2010, 03:20 PM

Quote:

Pick A Part had two Rex sitting in the yard

NO WAY!@!! You are in trouble if you're lying about this, but it looks like PAP got a LOT of vehicles lately because the backlog on the website only goes til May 17. Did either have climate control stuff? I decided not to bother getting any rear interior pieces, but if I can get them for junkyard prices I might as well I suppose. Climate control and lower dashboard stuff would be awesome... I won't be able to get there anytime soon though.. Next weekend at the earliest. Dang!

I got an offer for the XFi shell - $75. I heard scrap was at its highest ever though... Any idea what the yard would give for it?

Christ · 05-21-2010, 05:21 PM

Nah, they were there, but at the rates they get ravaged, I wouldn't suspect much would be there next week.

You can usually call and ask about parts, and they can tell you if they have any cars in the yard that reference to it. Most interior parts, they won't be able to tell you... however, if you just plain old ask about a CRX, they can tell you if one is there.

The guys that work there know what's in the yard, for the most part. I have no idea what pick a part gives for scrap, but last I knew, scrap cars were close to $300/ton in this area. If you got an offer of $75 from a scrapper, chances are, you'll get at least $125 if you go to a scrap yard with it.

Wonderboy · 05-21-2010, 11:55 PM

I took it on a tiny little maiden voyage up and down the street, but I forgot I had to bleed the brakes, so I had my friendly tenant help me with that. I got the tach to work (with the 4cyl > 3cyl error margin still present), Got the temp gauge to work, although I don't know if it is accurate since I'm using the CRX cluster. When I leave it running for a while and especially after I rev it up a bit, the coolant will spill into the overflow container and boil very violently, spewing steam. I have a feeling there may be something wrong, such as the thermostat not working. I got a legit CEL, but I forgot to hook up the diagnostic plug thing to jumper, so I did that, but haven't checked the code yet because I think the biggest concern right now is that boiling coolant.

The exhaust also has a number of leaks that will need to be fixed before trying to diagnose the oil smoke that billows out as soon as it's started. (I'm assuming the O2 sensor needs to be able to do its job, and once it can the smoke may go away). The smoke will sometimes go away for a while after holding the throttle higher (btw 2 and 3k rpm) for a while.

What should I do about this coolant issue - does it sound like a thermostat thing, or am I just a fraidy cat?

Christ · 05-22-2010, 12:12 AM

Swap your cap for a new(ish) one.

Test the temperature (with your hand) of the radiator hoses and the heater core hoses. If one of the radiator hoses is cold(ish) while the other one is hot, the thermostat has not opened. If the engine has been warm for some time, the thermostat is stuck shut. You can test this by putting it in a pan of boiling water. As the water in the pan reaches the stat's pop temp, it will quickly open (think "boing!"). If that happens, let it cool, and reinstall it. There is a chance it could have been installed backward previously. If the issue continues, at least you've eliminated the stat from the loop.

The engine will smoke until the rings seat. When it's at higher RPM, the smoke stops because you've burned it off the piston top and exposed walls.

The boiling coolant means you don't have proper pressure in the system somewhere. While the engine is cold, remove the radiator cap and start the engine. Check for bubbles in the radiator. If there are any, replace the head gasket, as it hasn't sealed properly. (You could also get away with using head gasket sealer, if you were so inclined.)

When the coolant is under pressure, it should not boil at all. If the engine isn't overheating, the cap should not open (the pressure in the radiator shouldn't reach high enough to blow the cap) and release coolant into the overflow tank. My truck does the same thing, and never sucks it back in, so I just run the coolant a bit low, and it's fine now.

You should not fill the coolant to the top of the filler neck... That's too full, and there will be no expansion room in the system for added pressure. If you keep adding back coolant when you see it blow off like that, it's going to keep blowing off as the pressure rises. Once it cools back down, the radiator will look like it's not quite full, which is normal. If the overflow tank inlet hose is not immersed in coolant (at the bottom of the tank) the radiator will not be able to pull in the dispersed coolant as it cools down, either. This is key to the overflow working properly, if you intend for it to do so.

Wonderboy · 05-22-2010, 01:39 AM

I've had a couple so please excuse me if I'm difficult to understand. The temp seems the same on the two hoses -really frickin' hot. I'll double check to see if they're different kinds of "frickin' hot". I know that thermostat test trick, I just want to make sure I only do that if I really need to since taking the thermostat out = mess. I ran it for a while today with no cap and with the front jacked up, but the way the engine currently idles makes a bunch of coolant spew out the top as though there were bubbles coming out, but I'm pretty sure there are no bubbles anymore.

My head gasket could very well be bad from making ghetto hole enlargements with a razor blade, but those holes aren't very big or close to each other, so I think the head gasket is pretty fine.

I'm going to look into letting the excess coolant spew out the top of the rad, then dispose/reuse it properly until it can't make it anymore