Yanmar 4JH3E injector pump rack is stuck

[skipperpete]

I tried shopping online for the correct puller but without success. I made one and used the plug as a sample for the thread then ran a hole thru the new plug and threaded it to accept the screw part from a small bearing puller.
It occurred to me at the time to loosen the inner hollow nut a few turns then screw in the large plug until it pressed on the head of the hollow nut but I never carried out the experiment... That timer is about $1400 on “Yanmarshop”

[tinho]

Originally Posted by skipperpete

I tried shopping online for the correct puller but without success. I made one and used the plug as a sample for the thread then ran a hole thru the new plug and threaded it to accept the screw part from a small bearing puller.
It occurred to me at the time to loosen the inner hollow nut a few turns then screw in the large plug until it pressed on the head of the hollow nut but I never carried out the experiment... That timer is about $1400 on “Yanmarshop”

Brilliant! So with all the warnings about keeping things absolutely lined up, If you remove he timer and its gear, doesn't that change the timing ? I put a large breaker bar attached to the main pulley on the front of the engine so it does not move, just as a precaution.

[skipperpete]

The breaker bar is a good idea but for peace of mind put witness marks ( white paint pen) on the timer and gear cover as well as the crankshaft pulley and timing case before attempting to pop the gear and timer off the taper, they should all be in exactly the same positions when the pump is back in and bolted up. I’m on the team that likes to line up the engine timing mark to TDC (or injection) before extracting the hp pump but it’s an old fashioned idea.
Also, it’s actually quite difficult if not impossible to change the timing by accidentally jumping a tooth by moving the pump gear when pulling the gear, but what I do worry about is the key in the pump shaft taper, I hate it when the key is upside down but I’ve never dropped one or even heard of one falling out, Yanmar made that key a good tight fit in the key way.
Good luck with the removal.

[Allied39]

OK, despite some of the abhorrent drivel I see on this forum I will go against my desire not to help a single sole on it.

So. when it is said, keep the timing right,,,,it means that the gear on the end of the shaft that comes out of the pump meshes with another gear you cant see. Those two gears have to stay meshed when you remove the pump.

The shaft that comes out of the pump locates in the gear you can see in one position only. Thats the important factor here.

So you need to remove the pump from the motor and keep those two gears meshed.

It is obvious that the 4jh3e and the 4jh4e differ slighly...but the principle is the same.If you have looked at the other threads its the same principle...different tool...well same tool little bit different design and threads.

Your engine has the spring loaded advance...but no matter, it all stays together...spring loaded advance and gear.

Start by turning the engine so that the key on the pump shaft is on the top, you should be able to see the groove when looking at the shaft end.

I would build a gear lock tool. it would have a plate that bolts into the 4 cover plate holes. It would have a large bolt the same thread as the cap nut that you pulled out. Inside that bolt would be another smaller bolt that screws through that and hits the pump shaft....with the bolt that holds the gear onto the shaft removed of course.

The large bolt would screw through the plate and screw into the gear. So now you have the gear locked in position. After removing lines, bolts and anything else holding the pump on the motor I would screw the inner bolt through the larger bolt. it would hit the pump shaft and the pump will pop free and be removed from the engine while the gears remain meshed.

There will be a key on the tapered shaft. Dont drop or lose it.

After the pump has been serviced, rotate the shaft so that the key will be on top. Then put it back together.

NOTE 1:If you cant build said tool, you really cant do the job. One fellow stated he did the job by stuffing rags in to hold the gear in place.... thats not how I do things....but I certainly will not say it cant be done that way or that he is not truthful. Just a really really half assed hope I get lucky way of going about it.

NOTE2:If the gears have become unmeshed at this point then you are in for a huge bill as you need a mechanic.....a good one who can remove the front cover ...well...basically the timing cover and re set the timing after the pump has been serviced.. A big job because everything in front of it has to come off.....and back on.

NOTE 3 I have re read this entire post and I cant explain it any better or clearer. If between this and the other threads you dont get it then this is above your ability. Which is ok, we all have our limitations.

But kudos to you, you are on cruisers forum and actually have a boat, that cant be said for all.

I hope you work this out.

[tinho]

Allied39,
Thanks for all the info. I had a yanmar mechanic come and remove the pump. sent it to get rebuilt Now the pump is back . The gear has the key set at the top , lets call it 12: o'clock. The pump came from the shop with the shaft key set at 3 o'clock. So I simply rotate it so it matches the gear at 12 o'clock and put it back? But then I get thinking, which cycle is the pump in? is it ready to squirt diesel on #1, 2, 3 or 4 line? and which stroke is #1,2,3 or 4 cylinder at ? I may be over thinking this but that is how my mind goes. I don't want to screw things up.