Hitachi Distributor mechanical advance

[omianan]

I need step by step instructions on how to remove the components on a Hitachi Distributor in order that I can get down to the mechanical advance mechanism to clean it and free it up so it works. The rotor will not rotate when hand pressure is applied to it, which indicates to me that the mechanical mechanism is frozen. I have found the instructions of 3geez for the removal of components on the Tec Distributor but have not been able to locate the same thing for the Hitachi. If it is on this site, can someone post the link to it. As you can imagine, the car doesn't rev much past 2K and then misses until the revs drop. Going up a hill is a real performance. I have put a new cap and rotor on the distributor and that helped. The shaft where the rotor slid on was also rusty so the hinged weights on the mechanical advance are probably rusted in place. I do have the vacuum advance connected so that may be helping keeping the engine running. I can get a new Distributor for $285 but would like to try and get this to work first. Thanks for any advice.

[Dr_Snooz]

Yeah, basically there aren't any instructions for the Hitachi distributor. It's not real hard to take these apart though. Just stay organized and take lots of pics so you can write a how-to for others to use. If you're real concerned, tear down a junkyard distributor first so you know what will break before breaking it on yours.

[cygnus x-1]

The 2g Prelude uses this same distributor (among others) and there is an exploded view in one of the service manuals. This one here specifically:

http://bluegreenlabs.com/Prelude/SvcMan/Prelude_Full%20Manual.pdf

It's in the "electrical" section. There are two other distributors detailed so you'll have to find the correct one.


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[omianan]

Thanks for that information. I have downloaded the manual that you provided the link to. Now I am confused. The cap and rotor that I got from the local Auto Supply fit the body and he told me that it was for a Hitachi. Looking at pictures on 3Geez and reading more posts it looks like the ignitor is mounted on the exterior for Tec's and the interior for Hitachi. My ignitor is mounted on the outside of the body. There is a bit of discussion on 3Geez about this and a lot of opinion on how to tell the difference. I have no numbers stamped on the housing that would indicate that it was a Hitachi (as read in one post). Anyway, I was busy changing the choke diaphragm assembly this morning and when finished that took the cap of the distributor again. I can turn the rotor some and can see the weights moving through a hole in a plate in the distributor. There are also no timing marks as indicated in other posts, no 15 degree mark or marks either side of a 15 degree mark. I know where they should be, but nothing evident.

The issue that I am having is that the engine cuts out at around 2500 rpm, starts missing. Sometimes seems to die out and then picks up again once the rpm drops. I am puzzled whether it is fuel starvation from the carb (vacuum leaks?) or if it is electrical. I doubt electrical, but unsure. I did have a vacuum leak in the choke diaphragm which is now fixed. I have the header pipe to change this afternoon then I can take it for a test drive.

As another post stated "I don't know whey we spend so much time and money on these cars when they are not worth anything to anyone". I guess I am like the rest of you guys, just want to keep these old carburetor cars going. :confused::confused:

[cygnus x-1]

Thanks for that information. I have downloaded the manual that you provided the link to. Now I am confused. The cap and rotor that I got from the local Auto Supply fit the body and he told me that it was for a Hitachi. Looking at pictures on 3Geez and reading more posts it looks like the ignitor is mounted on the exterior for Tec's and the interior for Hitachi. My ignitor is mounted on the outside of the body. There is a bit of discussion on 3Geez about this and a lot of opinion on how to tell the difference. I have no numbers stamped on the housing that would indicate that it was a Hitachi (as read in one post).


The guys at the parts store aren't always the brightest, and the interchange data in their computers is sometimes wrong as well. So if you want to know which one you have, go by the pictures in the service manual. Sounds like you have the right parts anyway.



Anyway, I was busy changing the choke diaphragm assembly this morning and when finished that took the cap of the distributor again. I can turn the rotor some and can see the weights moving through a hole in a plate in the distributor. There are also no timing marks as indicated in other posts, no 15 degree mark or marks either side of a 15 degree mark. I know where they should be, but nothing evident.


Sometimes the marks get filled in with oil/grease/crud and are difficult to see. You might have to go after the flywheel with a wire brush or scraper of some kind to uncover the marks.



The issue that I am having is that the engine cuts out at around 2500 rpm, starts missing. Sometimes seems to die out and then picks up again once the rpm drops. I am puzzled whether it is fuel starvation from the carb (vacuum leaks?) or if it is electrical. I doubt electrical, but unsure. I did have a vacuum leak in the choke diaphragm which is now fixed. I have the header pipe to change this afternoon then I can take it for a test drive.

Could be either. A weak coil or flaky ignitor could produce those symptoms, as well as a plugged fuel filter or malfunctioning carb.




As another post stated "I don't know whey we spend so much time and money on these cars when they are not worth anything to anyone". I guess I am like the rest of you guys, just want to keep these old carburetor cars going. :confused::confused:


They're worth something to us. :tongue:


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[ecogabriel]

I agree with Cygnus and the Dr. on what they said.

Since you already got the service manual and the exploded view, you may go ahead and take it apart documenting the process with photos, drawings, notes, whatever works for you.

I would like to volunteer taking a carbed distributor apart - it crossed my mind when I posted the TEC teardown - if someone from the ATL area wants to do it.

Since our cars are old (mine is 1986) and have been neglected for years you may encounter problems that become a compound of more than one issue at the time.
I would say make a list of the things that are not right with the car and attack them ONE at a time.

In my experience, those are quite good cars.

[Dr_Snooz]

The carbed cars got Hitachi distributors.

[omianan]

I found a number on the housing, it was covered over with crud. TD-44K. A search tells me that it is a TEC. As I have only had this car two years, someone could have changed it many years ago. 3Geez has good pictures and description for a tear down on the TEC. Before I start that process, I have switched the coil for a new one and will see how that performs tomorrow. Trying to eliminate the easy things first. I don't suspect the coil as it is my experience that a coil either works or it doesn't. Will post back again tomorrow with the results of the swap.

[ecogabriel]

If you go for the distributor, document EVERY step you take at disassemble. Also take a look at the bearing and the shaft seal. Both can be sourced (see TEC EFI teardown) but I am unsure whether carbed distributors use the same bearing. I found the guys at CBR bearing had bearings for Honda distributors (the 1990s ones are different -smaller) than ours and they are listed in their website; ours (EFI at least) was not listed but an e-mail confirmed they carried it.

[omianan]

I'm still tracking down possible easier solutions to my engine momentary (few seconds) shut-off at 2500 RPM while on the highway, goes back to normal after the RPM's drop. It does this without any movement of the throttle. It will do this every time I come to any kind of an uphill grade. The only time it doesn't do it is if I am going downhill, then it will go 3000+ with no problems. I read that the distributor is grounded to the block under the intake manifold to the block. I am going to have a look at that today to see if there is such a thing under the intake manifold. I replaced the intake manifold gasket last year and vaguely remember there being an "eye" wired into the wiring harness but can't remember if I reattached it to the block. I thought it was just a hanger to keep the wiring harness in order. I haven't read anything on 3Geez that talks about this ground for the distributor.

[POS carb]

sounds like the ignitor or coil to me (assuming you have adequate fuel pressure).
It could also be as simple as a bad coil to cap high-tension wire.
I think I still have a hitachi back home. I'll look for it and let you know.
The ignitors are expensive and hard to source, sometimes it is cheaper to get the complete distributor..
coils are cheap. you can hook up any 2-wire coil to these cars. pm me if you want instructions.

[Dr_Snooz]

When was your last tune up?