I have a 91 CRX HF that I just swapped to a D16A6. The motor was supposedly rebuilt when I bought it, although not fully put back together. The head was complete and bottom end complete and had to be joined. We managed to get it all done, worked our kinks out and got it to fire up and start.... The fun begins.

1991 CRX HF
D16A6 with Pm6 ECU and HF wire harnesses

Immediately there is a loud knocking coming from what I think to be the head. Check engine light came on and stayed on, along with the oil light. The engine code is 7, TPS. And the motor has plenty of oil, did too much to forget to put oil in it lol.

Any Ideas?? I am going to have a mechanic look at it, but I am totally stumped. Only thing I can think of is, whoever did the "rebuild" did something wrong. Just trying to see if I can get some ideas so that I can start looking into it.

Thanks in advance.
Over 40 hours this weekend and still can't drive it

 

Knocking is no good. When the block was seperate, did you bother to check the rotating assembly? Clearances and torques specs? For the head there isn't too much outside of adjusting valve lash BUT if you installed the belt incorrectly and didn't align the cam with the crank appropriately then that could be problem.

 

Not really sure if it is a true knocking noise or not, to me it sounds really loud in the valve cover area. Got to thinking, if the oil light is on, then there probably isn't any oil pressure. Which then makes me assume that could be the reason for the noise.

The head was already put together, not by us. But the bolts were tight so we assume they did it right. We made sure to rotate the crank so that the pistons were down when we put the head on. To avoid damage, once it was all assembled and we put the timing belt on, double checked that. Once it was together we rotated the crank and didn't hear any noises.

Hoping I don't have to rip the whole engine back out

 

D series are known for some valve clatter in the head. May want to do a valve lash as 24TEN suggested. Is the oil pressure sensor plugged in on the back side of the motor by the oil filter? It has 2 prongs on it. If that is unplugged, it maybe the reason why the light is on.

 

Never done a valve lash and assume that wouldn't be to pricey to get done by mechanic. Looked it up, doesn't seem to difficult.

As for the oil pressure sensor, we cut those wires to prevent us from breaking the thing trying to figure out how it came out. I connected the wires back up, maybe they slipped out. I will have to take a look at it later for that

Can't wait to get this thing running, did all this because the hf motor had a bad piston ring. As of now the problems seem worse on the new one lol

 

Personally I am not to fond of buying "rebuilt" motors from people unless it was done at a shop and have the receipt to prove it because people are dumb sometimes and fail to learn to put a motor together. I'v bought a "rebuilt" motor until the piston rings started blowing out out of the exhaust within the first 10 mins of the motor being started. Lesson learned.

Valve lash is easy. If you plan on taking alot of your issues to a mechanic, you may not want to mess with an older honda, as it may get pricey depending on the condition of the car. They are 20+ years old cars. Just fair warning you not trying to deter you from the car lol.

 

Yeah, not sure that I went the right route now or not. Guess we will find out, hopefully it's just simple stuff. But on the good side, my mechanic is my father in law

But I will go over there later to today to give those items a check and see if I can do the valve lash. Or I might have a huge list from the man by the time I get there lol

 

Are you saying that the head was installed with the crank not set to Top Dead Center (TDC)? If so, did you rotate it back to TDC before installing the belt? Also, did you set the camshaft to TDC before installing the head? If you just installed the belt as is with the pistons all down in the bores and the camshaft at a random spot I can almost guarantee you that you bent some valves when you rotated crank.

 

No we turned the crank to lower all the pistons (to make room for any valves that were open), then installed the head. We then turned the cam to TDC and then the pistons to TDC and installed the belt. That is all good.

Found out the problem, whoever rebuilt this engine didn't do a good job

I tested the oil pressure it barely climbed to 5 psi, so now basically it looks like I get to rebuild it right. Unless there is something some kind of simpler than ripping the engine out and getting oil pressure up. Oh forgot that is if there isn't any damage inside from there being barely any oil pressure.

 

if the oil pressure was that low and running for more than like a fraction of a second then your bearings are muffed. it has to come back apart unforunately

also, to clarify, the 2 wire connector on the back of the engine is the coolant fan switch. near it is a 1 wire connector with a plastic cover over it, that's the oil pressure sensor. the sensor provides a ground when the sensor detects extremely low oil pressure. if it was unplugged, the light would never come on.

 

Never done an engine rebuild, but I guess I don't have much of a choice. I assume I am going to need a full rebuild kit (around $400) that comes with pistons, gaskets, oil pump, bearings, and whatever other misc bits and peices. Doesn't include head rebuild, but I'm hoping I won't have to.

But what I am assuming is that since the head was port and polished and what ever else, that i wont have to get anything machined. More of a replace everything rather than fix everything as well. Any input is greatly appreciated.

 

If your doing the rebuild do it correctly and use OEM parts. You get what you pay for and you cant go wrong using the parts that were designed for the engine.

 

So buy this stuff from Honda? Or would an engine rebuild kit from someone else be ok.

 

I am wondering if there is any way to remove the oil pan and look around in there for damage. And possibly not need an entire rebuild. Since there was at least a little bit of oil pressure, more oil pressure at higher revs (according to mechanic). And the oil did manage to circulate around the motor. That maybe I might get lucky and just need to replace oil pump and feed.

 

But what I am assuming is that since the head was port and polished and what ever else, that i wont have to get anything machined. More of a replace everything rather than fix everything as well. Any input is greatly appreciated.[/QUOTE]

With what you have just found out about the bottom end do you really want to trust that the head was done properly?

 

i have a d1616 also and my cylinder 3 rod bearings kept shredding apart, i rebuilt the bottom end and sent the crank out to get resurfaced then when i put it back in cylinder 2 rob bearings shred. that could be your knocking sound cause my oil light and engine light kept coming on for that. to check if its a bearing just drain the oil and swirl your finger around and youll be able to see metal swirling around, thats how you know it would be a bearing.