spazwell

Here is the story first (history). My cousin has a 1993 Honda Prelude that had a 2.3L inline 4 cyl. The engine threw a rod and needed a new block. The car was at a mechanic shop in Longmont Colorado. The mechanic got an engine from a junk yard and put the DOHC head on the engine thus creating the Frankenstein engine with H23 head and the F23A4 block. My cousin drove it for a couple of weeks when it started burning oil excessively. The relationship between my cousin and the mechanic in Longmont quickly went south.
The car now comes to me to work on. The first thing I advise them to do, is to get the engine machined with new rods, valves, bearings, oil pump ect. I took the engine out, stripped it down, and sent it to a machine shop in Fort Collins, Colorado. I received the engine about a week later and installed the motor. Run up revealed that I had no oil pressure. I went thru all the elementary things involved with the oil system and found that all components are operational, but no oil pressure. I sent the engine back to the machine shop, and received it back again. Again no oil pressure.
This is when I start sticking my nose in the machine shop. I asked the question, “could the engine be rotating opposite from what the new oil pump needs”. It sounded like the silliest question but now it’s the reality of the situation. I took the oil pump apart and found that the engine would have to turn counterclockwise (standing at the pully side looking at the engine) in order for the pump to work. The F23A4 engine that is here turns clockwise (standing at the pully side looking at the engine), this is why the pump is not working. Believe me there is no mistake, it turns clockwise standing on the pully side facing the engine. I have double and triple checked this and did it all over again because I find it hard to believe that no one knows about this. Every Honda tech that I talk to, says that all the inline 4’s rotate counterclockwise and all the V6’s rotate clockwise in the Honda world, but here I am looking at one that doesn’t. I did find that this particular engine did come from Japan as a part of the, “here’s a cheap engine replacement and good luck with that, program”. I don’t know if that has anything to do with it. So, what I am looking for is a few answers.
1) What the hell am I looking at here? By that I mean this engine appears to be the only one in existence at this time until proven otherwise.
2) Where can I get an oil pump that works with this engine?
3) How accessible are the rest of the parts that are limited by rotation, alternator, water pump, steering pump, A/C compressor,,,,, dear god! Do I need to tell my cousin that he needs a different engine/trans?

Thank you in advance for any intelligent response.

v4lu3s

the f23a4 came out of a us market accord and rotates counter clockwise just like every other F series engine in an accord. rotating clockwise will cause timing belts to skip teeth and jump time and destroy the engine.

spazwell

I have heard that more times than I can say. I wouldn't believe it myself if I didn't see it. I have a honda guy that is eager to see it, as he says it is impossible. The machine shop is going to put it back together and send it back to me. I will install it knowing I will not have oil pressure. If everything is as it was, I will take video of it. Outside of that I'm at a loss. I looked at the rotation and verified it over and over again, but Im not above making mistakes. When I get the engine back, I'll check again. thanks though

v4lu3s

if you look at the timing belt side of the engine you should have the crank snout with timing gear at bottom, above that is the timing tensioner, to the right of that that water pump, then up to the camshaft, than a straight shot down to the crank.

this set up is designed to rotate counterclockwise, with any slack on the timing belt being pushed to the tensioner area, which if you had a manual for a 98-02 f23 powered accord you would see that adjusting tension is doe exactly that way.

gstrudler

Whoever said that all Honda 4's rotate the same way has no idea what they are talking about. All K-series engines and the f20/22c rotate clockwise instead of CCW like the older Honda 4's.

I don't think it would be a direct fit, but I suppose you might have the oil pump from say the k20a3. Check pictures on eBay or somewhere else of the f23 oil pump and see if it looks the same or not, and/or order a new one if you're convinced it runs the wrong way.

gstrudler

Since I was just in the AM forum and somebody else had an oil pressure problem with an F23.... they were trying to use an h22 oil pan and it apparently is not compatible with the f23 oil pickup because it blocks it. They were getting basically 0psi at idle, and about 10-15psi at 3k. Swapped oil pans to the stock f23 and everything was fine. Sounds like this could be a possibility for you as well. The original shop probably used the h23 oil pan and it may not be compatible with the f23 pickup.

spazwell

Thanks to all for the help. I'm on the same page in thinking that some how the machine shop my have ordered the wrong pump. We tested the oil pump outside of the engine and it works great when rotated the right way. Once installed we can't even get oil to the filter, and all passages are clear and clean. YES O rings were checked as well, and even if the O rings were messed up I would still get some oil at the filter. I'm a aircraft technician and have worked on Gulfstreems (about a 60 million dollar aircraft) I have never had something so simple as an oil system (internal mind you) in a car stump me like this. Thanks again guys and gals (if appropriate).

spazwell

Whoa, oil pan? I like that one, it would be difficult to see and would remain in hiding until you install a camera in the pan. Funny that you mention that, cause it did get a new oil pan and since then the problem has been there. I may be mistaken about the rotation, although I swear it was turning clockwise, it could be my old eyes and vertigo of the white lable moving so fast. The oil pan will be inspected further, its much cheaper than an engine. Thanks again, that's the answer I believe I was really looking for.

v4lu3s

is the oil pan a sheet metal or cast aluminum oil pan?

spazwell

Thanks gstrudler for your input; yours seems to be the answer I was looking for. The mechanic at the mechanic shop apparently ordered an oil pan for a 93 Prelude which is the H23. At first they didn’t think it would make a difference. I told them if they wanted to take on the responsibility of being the engineer and guaranteeing the part, they could do so, otherwise I wanted an F23 oil pan attached to the F23 engine. In the H23 pan, the pick up tube sat perfectly in the bottom, all sides of the pick up tube. In the F23 pan, the pick up tube sits on the bottom but it’s at an angle. I think that the problem is solved, unless otherwise disputed. Thanks again for all the help from all.
P.S. I will get my eyes checked for the apparent misunderstanding of the rotation of the engine. lol

gstrudler

Glad I could help; never would have guessed if it hadn't popped up in the All Motor forum. Happy coincidence for you; hope that solves the problem.