Newly rebuilt motor with a healthy knock

[JAy]

Hey All,
I just put the 2.25 petrol back in my 73 series 3 88" and she has a pretty bad knock coming from the bottom end. Here's the details:
I finished the rebuild about 3 years ago, and the motor has sat dry on a stand ever since. I didn't try to start it, but I did turn it over using the nut on the front of the crank now and then. Pretty much everything was replaced or machined. I did most of the work, and it's my first rover engine rebuild, but I have rebuilt plenty of motorcycle engines so I'm not totally green. I checked all my bottom end bearing clearances with that squish tape stuff before final torquing. I had the machining done at a shop that knows rovers well. They also installed the floating pistons on the rods and did the valve work. During machining the machinist told me that I had a bad rod, and I got another, new to me rod from a fellow rover owner near by. I got the motor back into the truck today and fired her up. She pretty much purrs except for a loud knock coming from the bottom end. Is it possible that this noise will go away with run in? (wishful thinking) Or is there anyway I can identify the noise and fix the problem before my motor blows up and I have to start from scratch?

[Terrys]

Jay, As I'm sure you know, knocks are almost always a rod to crank noise, and not a crank to block noise. I would suggest you pull the plugs and with your handcrank, rotate the engine as smoothly as you can through as many revolutions as you can. As soon as you detect, either by feel or sound, the noise, stop and check the orientation of the rods. This will pretty much narow it down to 2 pistons.
If the noise will not manifest itself unless it's running, then it's probably a big end rod bearing. I feel your pain, but don't hope it will go away. Clatter from hydraulic dry lifters goes away. Knocks only stop when there's been a catastrophic failure.

[rovertek]

the first thing you want to do is fit up a (good quality) mechanical oil pressure test guage to the banjo fitting on the oil filter housing to see if you have sufficiant oil pressure

[jp-]

Check the oil pressure, but be prepared to get your hands dirty again. Running an engine with a knock isn't going to do it any good.

Something else you might want to check is that you installed the crankshaft thrust washers. Very easy to forget.

[msggunny]

This isnt going to help you but i gotta ask everyone else's oppionion and since you started the thread i thought i might hi-jack it.

My 2.25 makes a loud ticking noise too near the bottom end, i havent been able to locate it exactly though. A few months ago when i had the exhaust off i couldnt hear it when it was running. Keep in mind that i dont have a regular exhaust mainfold, but a header and the collector had to be bent a bit IOT allow for clearance for the muffler.

Could it be the exhaust making the noise?

Do those stethascope things for cars work? Thinking about getting one and taking the exhaust off again to see if it will pick it up.

If not, i will just run the piss out of it like i do and wait until it blows up. It will give me an excuse to find a V8 and start the swap.

[JAy]

Thanks for the suggestions.
I'm pretty sure I installed the thrust washers, it was a long time ago, but I do remember paying pretty close attention to all of my manuals when doing it because I was concerned I was going to mess something up.
I have a spin on oil filter adaptor and a mechanical gauge on the unit because my old sending unit was damaged. The mechanical gauge wasn't reading anything but I thought that was probably from a leak in the line between the engine and the gauge. I stopped the motor before I could troubleshoot that because of the knock. There was oil in the line, so I know the oil pump is pumping, I just don;t know how much it's pumping. Is there any possibility that if there is really low oil pressure and I fix that, that the knock will go away? I checked in the valve cover and there is oil on the rocker arms, but not oil all over the place like I would have initially expected. But I have never had the oportunity to look into a fresh valve cover before so I am not sure if that is normal or not.