Hello--

Recently got this '82 prelude, and I am quickly learning how little parts are left for it The suspension is blown to hell, and there are no replacement parts for it whatsoever....but onto the real issues.

The engine starts and runs, but it has a few concerning issues that I think are all related. First, it has issues revving. It'll either: rev up to 4000, start popping in the carb and wont go any higher, or it will: rev up to 5000, hesitate for a split second, then go up to the 6000 redline. This makes me think it might be a carb issue, but the second issue below makes me think otherwise.

Also while I am revving it, there is a very loud ticking noise coming from the top end of the motor. The noise is inconsistent and quiet until around 4000rpm where its the loudest and most consistent. To me, it sounds like either a loose as f*ck valve, or detonation. I have adjusted the valves twice now with no audible improvement. I went to check timing, but I am confused at what I'm seeing.

In the FSM, it shows there being a "T" and then a line with a number next to it on the flywheel. This is what that looks like:
V
T.. l
....12
However, mine looks like this:
....V
l ..T ..l
(Lines on either side of the T, and V is the pointer)

So, with the vacuum advance disabled, slow idle, this is what the timing looks like:
.....V
l.. T.. l

With the vacuum advance connected, slow idle, heres what it looks like:
..............................V
l.. T.. l

I'm not sure if theres another timing mark I missed (need to check tonight with a 2nd person) but I have a feeling my timing is getting pushed waaaaay too far advanced. I can get video of the car tonight if that'd help with the diagnosis.

Thoughts? Can the vacuum advance really push my timing so far that it'd make the engine to start detonating? Any idea why it has issues revving?

 

Hello,

Let's take a few steps back. How long have you owned it? How long has it had this problem? When was it last tuned up? Do you have a service/repair manual -- and tools?

 

Dang, 21 days for a response?



Maybe 2 months?

Since I got it

I believe the previous owner did plugs wires cap and rotor as they all look fresh.

I do have the service manual and tools.

I've since concluded its not timing thats causing the knocking noise. No idea where the other timing mark is as I had a friend rotate the flywheel while I watched it and theres no mark aside from whats listed in my first response.
As for the revving issue, I'm pretty sure the carb just needs a rebuild.
As for the knocking, I think the rod bearings are toast. While the car doesnt burn oil, I've heard that these motors have **** poor oil pressure at idle, and 123k miles with bad oil pressure will inevitably wipe out rod bearings.

 

Swapped new rod bearings into it, as well as a carb rebuild, timing belt, ignition parts, etc. Seems to run better as now itll happily climb to ~5500rpm before it cuts out. I know it prolly shouldnt do that...but i dont care at this point. It's close enough to the 6k redline.

The knock seems to have gone away, though something in the valvetrain is loud. I've adjusted the valves several times already and its still there. I read that the aux valve retainers can get noisy when they fail, and it will start burning oil like crazy. Mine has yet to start burning oil so... *shrug*

 

Just wanted to post an update and conclusion:

Found the issue with the loud valvetrain and the engine cutting out.

Loud valvetrain was due to a bent rocker arm. Yay... Managed to get it adjusted-ish and most of the noise went away.

Cutting out--While oogling the bent rocker arm, my roommate noticed that the #4 cvcc lobe was completely wiped and the exhaust lobe was about 1/2 gone. Seeing as finding a replacement head / valvetrain parts was going to be impossible, I recalled someone on the G1 prelude fb page posting about a free '81 engine. Unknown condition, but free. Made the 4hr roadtrip to get it, as well as some body parts for my car. After doing seals, cvcc valve rebuild, rings, etc. the engine runs soooo smooth now. So smooth that I took it on 2 8 hr road trips all within a week.

I did buy a nos rebuilt carb as well to replace mine, thinking mine was having issues, but turns out the nos carb had more issues than mine did. The accelerator pump was not functional, and it sputtered badly while cruising. I replaced a leaky diaphragm on the original carb and it works as it should. Fast idle, choke, smooth secondary transitions...everything

Future plans are to get the bc coilovers, drop it a hair, put my appliance mesh rims on it, fender flairs, and redo the paint with candy purple. But for now its my daily when the roads arent salty :D

 

Thanks for the update.
P.S. If I can still find parts for my '76 Civic -- like suspension parts -- I bet you can too!

 

ha youre funny. basic maintenance parts for the EK1 and EL1 are becoming very hard to find. Suspensions parts? what suspension parts? lol. All the shock cartridges, if you manage to find some, are shot from sitting, and nothing crosses over from the civics and accords of the era. The bc coilovers are for the 80-83 civic, and must be used with an adapter sleeve.

I managed to cram tercel cartridges in the rear struts, and from a lead told by nathan mitchell, I managed to retrofit late 90's vw beetle (or is it bug?) shocks for the front.

 

I just sold a pair of NEW, FRONT MacPherson struts on EBAY that I didn't need. I think I still have four used ones around here somewhere. There are some in junk yards -- finding ones that work?????

Stuff shows up on EBAY every day!

 

not for the prelude. i found someone who had a set of nos front cartridges, and he refunded my money as when he checked them, he found that the seals failed from sitting. thats the issue with ancient nos shocks. if the shock rod sinks when you pull it out, or has no resistance, theyre bad, just like the ones you have for sale on this site. the first gen prelude doesnt have a following whatsoever unlike the old civics.