cfahamilton

I have a 97 Civic hatchback. It is barebones stock. Manual trans, no power anything, no A/C.

Symptoms: It shifts normally into all gears but fifth. It grinds going into 5th unless I manually synchronize the engine to vehicle speed. To get a smooth shift I double clutch to let the engine speed normalize and then shift into gear while the vehicle is going between about 55 and 62. (Something like that. Its been a while since I drove it.)

Background: The car was a DD for me, never raced or driven hard but i didn't have it that long and don't know its prior history. It overheated one day and developed a bad bottom end noise (damaged crankshaft bearings). I bought a used engine and swapped it out but kept the original trans. The 5th gear problem was present immediately after the swap (but not before the swap even after the overheating incident).
From looking at other threads, it seems that it could be a bad synchro, a bent/worn/broken shift fork, or a problem with the linkage.

I'm hoping someone with more experience can look at my particular symptoms and tell me which is most likely.

Synchros seem unlikely because I did not have the problem prior to the swap. Nothing should make them wear out overnight.
A bad shift fork seems like a possibility but I don't know what might have caused the problem.
Something wrong with the linkage also seems possible but I don't know what to look for or how to correct it.

I did have some trouble getting the bitch pin out of and back into the linkage when I did the swap. Could the pounding to get the pin out somehow damage something inside the tranny?
(I wasn't missing the mark or using a sledge but I did have to hit it pretty hard before it started to move. there is no visible dame to any part of the linkage.)
If it was a linkage problem wouldn't it also mess up the shifting for the other gears?

I really just want to sell the car. I don't want to hide the problem from the buyer but I also don't want to have to lower the price a lot because of it. It's not in great shape and not worth that much to begin with. If I can fix it first without spending a lot of money I will.

Any help would be appreciated.

94EG8

As a rule grinding is due to a banged up sleeve and hub and sometimes a flattened out synchro spring. The fact that it's grinding immediately after an engine swap is interesting.

TomCat39

If there was an issue with the throw out bearing and bearing fork, I would think it would grind always. And it's the one area that is semi dis-assembled on an engine swap.

cfahamilton

Thanks for the reply 94EG8, I have been doing some research so I can visualize the parts you say are likely the problem. If it's what you say, it sounds like a typical rebuild replacing seals, bearings and synchro gears would not solve the problem. Is that correct?

I was reading other threads that ask about how it shifts when parked and off. In this scenario it is very easy to shift into 1st through 4th but more difficult to shift into 5th and reverse. In fact, sometimes it's impossible to get it into 5th unless I shift partially or fully into reverse first. Reverse is also very difficult and may require several atttempts.

Does this shed any light on what the likely problem is? Anyone else want to chime in? Thanks for any help you can give.

cfahamilton

Thanks TomCat, I was referring to the shift selector fork for 5th & reverse internal to the transmission, not the throwout bearing fork. I appreciate the response though.

TomCat39

Thanks, I forgot about that detail when replying. My error.

94EG8

That is correct. Most of the time, especially on a D-series the synchros will be good as well as most of the bearings. In a case like yours if it is indeed the sleeve and hub your cheapest option is a probably to go through a company like Synchrotech or Gearspeed and order the sleeve and hub.

Reverse especially tends to be a challenge with the car off or bench shifting. Honestly it doesn't mean a whole lot most of the time.

cfahamilton

Ok, It looks like I'll have to open it up and see what I've got. I was trying to avoid that. Is it at all possible that something in the linkage is out of whack and I could fix that without having to drop the trans and open it? It's just nagging at me because I don't remember the problem being there before the swap. Thanks for your replies.

94EG8

I can't see any reason why it would only give you issues going into 5th if it was the linkage.

94EG8

I can't see any reason why it would only give you issues going into 5th if it was the linkage.

jdblock

Thought everyone knew to put the car in first or second before going to reverse. Just a Honda thing.

cfahamilton

Here's a thought. Could it be grinding now because when I swapped the engine I changed the transmission oil and now there is a different viscosity than there was before?

I think I put 10w30 in it because that is what I saw was recommended. Now I'm reading that it should be only Honda MTF. In any case, should I be looking to put a thicker or thinner lubricant in it?
It would be great if a fluid change could help me avoid a tranny drop & rebuild.
Any thoughts on this?

DumpdEJ6

10w30 is pretty similar to MTF, lots of people run 10w30 in their transmissions without issues. MTF is a little better though, it's what I use. I would say it's kind of a long shot that it helps, but then again, it's a lot less work than removing the trans and taking it apart, so I'd say it's worth a shot. It's not like you have a lot to lose by trying.