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Yeah, may be around the fan... as it is paint in black. I guess it could holding some power steering line.

The other one may be behind intake manifold holding Power steering.

I am sure you will figure it out when you put things together. I was in the same boat when I did of what you currently do. Gluck
 

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Discussion Starter #42
That silver bracket mounted on top of the fuel injector harnesses, holding a hose. The other one, well that's just going to figure itself out.

The engine's back together and it runs! However, it wasn't without some near heart attack-inducing moments. I initially did a compression check prior to startup and had the following numbers (psi):

1) 180
2) 50
3) 75
4) 185

At that point I completely lost all hope. I spent all this time, didn't cut corners, meticulously followed every step in the manual, and used the best materials around. I was ready to give up and just throw the spark plugs in and fire it up; see what two cylinders would sound like.

I cranked the engine a bit, gave it some gas and then the engine gradually started firing on all four! I let it idle and it hovered around 1200rpm. I haven't heard an old Honda engine in some time, so i wasn't sure if it was running on 2, 3, or all 4 cylinders. I disconnected a spark plug wire and sure enough, three cylinders was very different.

I shut off the engine and hooked up the compression tester again, and all four were now around 185-195psi. My guess is that the valves had some junk in the seats, and that a couple of engine cycles blew them out. Hopefully it was just minor debris that didn't score the cylinder walls.
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Prior to starting, valves were adjusted to .006" for the intake and .016" for the exhaust, and I'm reminded of how distinct these engines tick.
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I had taken apart the IACV to clean, and the old seal was all hardened, so I had to glob some Permatex to fix a water leak.

Going to check for leaks once more today and then put the tires and splash shield on before going around the neighborhood. After that it'll be time to put the new tires. For now, this is how the engine sits.
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Discussion Starter #43
So, I had made one fundamental error, and that was adjusting the valve lash incorrectly. I read the specs correctly in the FSM, but misread my feeler gauges, and was got mixed up between the metric and English units. Therefore I'll have to tighten-down those gaps later.
 

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Discussion Starter #44
So, after adjusting the valves (while engine was dead cold), I proceeded to start it up last night. Rough / stumbling idle ensued. I have no idea what could have created it. My clearances were to spec (.005" for intake, .007" for exhaust), and I had double checked to make sure i had all hoses reconnected (I didn't disconnect any connectors to my knowledge). After a few minutes of rough idle, it settled back to about 900rpm. If i gave it some gas, and then let it off, the engine would want to die, only to put put its way back to idle. My TDCs are all lined up (flywheel mark, cam gears up), and when I pulled the plugs two were rich and two were lean. Not sure why this is happening here. I did a sanity check and checked compression this morning (cold engine again) and had good compression across, so there's at least some closure there.

Not sure if it's just a coincidence with valve adjustment and lousy idling, but looking for some help here. Much appreciated.
 

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Discussion Starter #46
I only started it a handful of times since putting it back together, so I never got a pattern of cold start RPM characteristics. I did notice it didn't go to high idle (~2000RPM?) at cold; rather it'd just be around 1200, and then eventually drop to ~850RPM.

Same with yesterday, it wouldn't sputter its way to 2000RPM, it'd just sputter around 600-1000RPM. I'll give it some gas and it'll rev smoothly, but then hesitate again when i let off, until it's warmed up.
 

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My guess it is not related to valve latch adjustment. Do you happen to have spared injectors ? may replace those correspond lean or rich injector and see any different.

Also was it bouncing idle or stay high and going back to 900rpm ? IIRC, there is a FAQ thread to fix this bouncing idle. Also, give TB and IACV a clean as it would smooth idle a bit.
 

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Discussion Starter #48
I guess I could check the IACV and throttle body again, I cleaned those before installing. I literally took apart the IACV to clean the insides, where the coolant flowed through. I had to RTV that plate with the existing gasket as i couldn't find replacements online.

I seriously hope it's not the injectors; the car runs fine at higher (2000) RPM. The idle was bouncy, it wasn't one of those "high, and then low, and then high" types.

Does the IACV "reset" if you disconnect it?
 

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2 cyls are leans and others are rich indicates fuel mixture (and/or sparks) are not consistence between cyls, hence I suggested injector, IACV, TB and distributor as they are all to have some impact on running idle as well.

Also, do you have spared spark plugs or swap them around and see if they are the problem.
 

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Discussion Starter #50
At this point I’m starting to get pretty frustrated. In addition to the idle issue, I have a rather large water leak somewhere. It seems to leak when the engine is warmed up. I still have good compression across, but is it possible to leak coolant while maintaining cylinder compression? Sean, looking for some support here since you’ve probably done a few head gaskets yourself. My head gasket orientation is correct as can be; it can only go one way.

With the idle, the IACV is working because the engine stalls when I disconnect it. I hv also backed the idle screw a bit, and that helped, but it’s definitely still running rough. Further, I checked the plugs and they’re all seemingly lean now.

What gives??
 

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Let's focus on the leak for now. Need to identify where leaking are which is not too hard. Also, is water has some oil in it ?
 

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Discussion Starter #52 (Edited)
At the time, I had an oil pan under the car with engine oil in it, so I was not able to clearly see if there was oil in it. The coolant in the radiator is clean. When removing the engine oil cap, there's a small bit of smoke. I shown a a flashlight inside the inlet and the oil was still golden, so that's good.

It does not seem like the water is leaking in the front of the engine (by exhaust manifold), more on the passenger side, under the distributor, near the black coolant pipe. I had replaced a number of hoses there, and they seem to be holding up, but I'd have to remove the intake manifold to look deeper. I might start the car up again and try and trace it.
 

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Hopefully it is not head gasket.

If leaking is not obvious from the front, I suggest go under the car see where the leaks are. Most common leaks are at Thermostat housing (distributor on pax side), heater inlet/outlet hoses connecting to the heater valve (at the firewall), various oil and power steering coolant hoses (connected to the engine black metal coolant) and they are below the intake manifold; and finally and hardest is at the Water pump and its o'ring connecting to that black metal hose.

PS: btw, coolant may sometime also impact idle as well, check the flow of coolant hoses connecting to TB and IACV.

Hope this helps!
 

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There's a freeze plug on back side of motor ifnim not mistaken off centered to the distributor side...known to leak after awhile. May worth a look
 

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Discussion Starter #56
Found it, and it was such a rookie mistake. It was leaking out of the thermostat housing because I had removed one of the nuts prior to getting the head machined. The flange on the nut was in the way of planing the surface, and I never tightened it back down. The engine's 18degrees really threw me off, leak from the side, trickle along the block towards the rear, making you think it's coming from the back. Tightened that down, and no more leak.

Now, time to figure out the dang idle. It does not high idle when cold. The cylinders has 165-175psi when cold, so the engine is theoretically good. I have sprayed brake cleaner all over the intake manifold in trying to find a leak, no effects. I have checked the fast-idle valve, and it's every-so-slightly loose (one thread shown above the wax valve), and I have unscrewed the idle adjust screw quite a bit. The IACV "works," as the engine stalls when I disconnect the connector. I have burped the coolant using the screw next to the coolant temp sensor and jacking car higher. Once warmed up, it idles "fine," I suppose. It does not hesitate when I give it gas, and it revs smoothly at 3000rpm. No CELs either. I unplugged plugged the air hoses from the emissions box and the engine would, respectively, raise to a higher constant idle. Reconnecting the hoses would resume the lower, rough idle.

I could supposedly hit up the troubleshooting flow charts in the shop manual, but hoping folks here could provide some quick words of wisdom.
 

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Discussion Starter #59 (Edited)
Dano, i had originally adjusted them to .016", but then realized I was looking at the wrong units on my feeling gauge! I was looking at the metric numbers in the FSM, and realized I was using the English units on the gauges. The ticking was loud, but it idled okay.
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Since then I have adjusted it corrrectly, about .007" for the exhaust and .004" for intake. My thinnest feeler gauge is a .006" so I use that as a "go" for the exhaust and "no-go" for intake. I first make the intake gap drag slightly at .006", then tighten the screw a quarter turn, as that much rotation roughly translates to .002" gap reduction, thus theoretically reducing to .004".

Please correct me if I'm wrong with these spec.

Previous owner of this car, duckeedoug, said he never had any of the weird idle issues I'm currently seeing. During his ownership it'd cold idle at 1500, then slowly drop to 700-750 at warm idle.
 

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Discussion Starter #60
Also, is the air filter supposed to mount this loose inside the air filter box? It does not seem to seal whatsoever. The clamp securely holds the filter, and the filter "holds" the lid for the filter box. Thing is, the filter has wiggle room when the lid bolts to the box. Am I perhaps missing a spacer or the like?
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