89 accord timing

I hope someone can help me figure out this issue with my 89 accord lxi sedan timing. It knocks in hot weather and I want to retard the vac advance a little more. The timing is supposed to be 15+/-2 btdc with hoses on. The most I can retard it is about 16-17 degrees, barely in range. with vac hoses disconnected and plugged it is supposed to be 4btdc, but at the proper vac advance, I am at TDC. Does anyone know how to back off the vac advance without affecting the plugged (no-vac) advance?

Reply to
los via CarKB.com
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Actually, I am getting a funny feeling. Pinging isn't a normal thing in '89 Hondas (or at least we don't hear a lot about it), so I'm wondering what is going on. You shouldn't have to mess with the advance.

Did it always do this or did it start after some work was done (or maybe the car is fairly new to you and the history is unknown)? Is the temperature guage reading normal - whatever it reads in cool weather? Finally, to ensure the problem is detonation (which is affected by timing) and not pre-ignition from hot spots (which is not affected by timing), you can run the tank down fairly low and refill with premium. If the knocking is the same with premium timing changes won't affect it and you will have to pursue decarbonizing. Of course, if the engine is running hot in hot weather that is the place to start.

Mike

Reply to
Michael Pardee

Good thinking, Mike... another thing to keep in mind when adjusting the timing is that the vacuum increases with RPM, and thus advances the timing further. It's important that the engine be at the specified idle when checking and adjusting the timing - on your car, depending on the exact engine, it should probably be around 700-800 rpm.

Reply to
Matt Ion

Mike / Matt: Thanks for responding. History. Bought used in 1994 with 55k miles. I had a good garage do the 60k service at 72k. I had a schlock garage do the 120k service at 140k. I assumed that they did the coolant. They did not. It went acid and killed the cooling system. I replaced the radiator, thermostat, water pump, and hoses and flushed the rusty water as well as I could, but too late. I cracked the head at 186k. Got a rebuilt head and new pistons and cylinders installed. A radiator cap that could not suction from the overflow led to coolant loss and a blown head gasket at 212k. I replaced the head gasket myself and blew out about 2 quarts of rusty crap from the block in the process. Very little carbon on the head (especailly number 1 and 2 where the gasket blew). The temp gage stays low even when blowing head gaskets. Now at 218k it runs great, but it knocks as always going up hills in the heat. High octane gas does quiet the knocks. To hit Matt's question, I checked the timing at about 800-850 rpm. It bogs a little when I check the no-vac advance. If I set it any more advanced than the maximum retard I can get, it knocks worse. Most of the time it runs fine. It just knocks briefly if I do jack-rabbit shifting or knocks pulling grades in dry heat.

Incidentally, I am replacing they front crank seal tomorrow. Why did I not do that with the new head gasket? A mechanic convinced me that hondas never leak from the crank seal even when they are bad. I replaced the water pump seal and oil pump seal so I think it must be the crank seal, so it's back under the hood for me. The timing thing still confuses me.

-Carlos

Michael Pardee wrote:

Reply to
los via CarKB.com

Only other thing I can think of, is if the ignitor/stator assembly (inside the distributor) is loose, or the air gap between the stator and reluctor (the components that provide the actual timing signal) is too small and is thus triggering the timing too soon...

I can't find an actual spec for the air gap, but there's a diagram of it here, to give you an idea of what you're looking at:

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If the stator is loose or out of place, it could also be affecting the timing. There's a brief bit on checking and adusting it here as well:
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Reply to
Matt Ion

you should post to message boards at:

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That is the site for 3rd generation Accords.

Reply to
jay420

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