Ruggerini RM90 push rods?

[jamie N]

I've taken the head off of the engine to replace the gasket. The push rod orientation is fore/aft off of the cam on the crank, but the tappets are side by side, which I didn't notice until the head was free, and I didn't see which way around the push rods go. This'll make sense to someone with the knowledge of these old engines, and I'd appreciate the help, otherwise I've got to guess which way they go, with the possible result that the head'll be 360° out, which would present a new issue!

 

[coopec]

It doesn't tell you in the manual? Not sure whether they want an arm and a leg for these manuals.

https://www.manualslib.com/products/Ruggerini-Rm-80-3826169.html

https://www.manualslib.com/manual/826646/Ruggerini-Series-Ry.html

 

[VicS]

I've taken the head off of the engine to replace the gasket. The push rod orientation is fore/aft off of the cam on the crank, but the tappets are side by side, which I didn't notice until the head was free, and I didn't see which way around the push rods go. This'll make sense to someone with the knowledge of these old engines, and I'd appreciate the help, otherwise I've got to guess which way they go, with the possible result that the head'll be 360° out, which would present a new issue!

If the RM90 is the same as the RM 80 in coopec's link although I understand what you men about the push rods being fore and aft of each other and the rockers and valves being side by side I don't see how you can put it together incorrectly.

I guess you mean "the head will be 180° out" not "360° out" if you turn something 360° you will have turned it a complete turn and be back where you started.

If you fit the head 180° out, even if that is possible, nothing else will fit.

It is obvious which valve is which valve is which and if it is necessary to determine which push rod is which can can do so by rotating the crankshaft. There will be two consecutive strokes, the compression stroke followed by the power stroke during which both valves will be closed. The next stroke is the exhaust stroke during which the exhaust valve will open, allowing you to identify the exhaust push rod. Finally during the fourth stroke, the induction stroke, the inlet valve will open allowing you to identify the inlet valve push rod.

Fit the rockers so that the exhaust push rod operates the exhaust valve and the inlet push rod operates the inlet valve ( I doubt if you could get them reversed anyway)


I fancy you are overthinking this. I suspect it will only go back together correctly, but do you know torque settings and valve clearances etc.

 

[RichardS]

If the RM90 is the same as the RM 80 in coopec's link although I understand what you men about the push rods being fore and aft of each other and the rockers and valves being side by side I don't see how you can put it together incorrectly.

I guess you mean "the head will be 180° out" not "360° out" if you turn something 360° you will have turned it a complete turn and be back where you started.

If you fit the head 180° out, even if that is possible, nothing else will fit.

It is obvious which valve is which valve is which and if it is necessary to determine which push rod is which can can do so by rotating the crankshaft. There will be two consecutive strokes, the compression stroke followed by the power stroke during which both valves will be closed. The next stroke is the exhaust stroke during which the exhaust valve will open, allowing you to identify the exhaust push rod. Finally during the fourth stroke, the induction stroke, the inlet valve will open allowing you to identify the inlet valve push rod.

Fit the rockers so that the exhaust push rod operates the exhaust valve and the inlet push rod operates the inlet valve ( I doubt if you could get them reversed anyway)

I fancy you are overthinking this. I suspect it will only go back together correctly, but do you know torque settings and valve clearances etc.

I don't know that engine but if you follow Vic's instructions you can't go wrong .... and next time you dismantle anything and don't have a manual it's best to make sure you take lots of photos. Phone pics are usually fine. I had to fit new HT leads to a car yesterday which involved draining down the coolant system, removing the exhaust downpipes, exhaust manifolds, intake plenum, alternator, polyvee belt, throttle and cruise control cables, intake ducting and secondary air intake systems. Once you have half the engine in bits on the floor just to replace 8 simple cables, you are grateful for phone cameras. :encouragement:

Richard

 

[jamie N]

Thanks for all of the replies. When I stated that the head was 360° out, I wasn't meaning the orientation of the head, but the rotation of the crank on this 4 stroke engine. I agree fully about the pics of course, but hindsight etc.etc. On any engine that I've previously dismantled and repaired, it's always been totally obvious which way around the pushrods go; this engine is Italian though, and they fit equally well into either tappet.
In the manual that I have, which is more an owner maintenance item, the clearances (0.15mm) are given but not the torque on the head nuts, these I've taken from my other engine's manual at 30 N.m.
Thanks for posting the manual link Coopec, but the 1st is the parts manual which I've got, and the other's for a different engine, but on page 7 of the parts manual, it 'sort of' shows the issue.

 

[VicS]

Thanks for all of the replies. When I stated that the head was 360° out, I wasn't meaning the orientation of the head, but the rotation of the crank on this 4 stroke engine. I agree fully about the pics of course, but hindsight etc.etc. On any engine that I've previously dismantled and repaired, it's always been totally obvious which way around the pushrods go; this engine is Italian though, and they fit equally well into either tappet.
In the manual that I have, which is more an owner maintenance item, the clearances (0.15mm) are given but not the torque on the head nuts, these I've taken from my other engine's manual at 30 N.m.
Thanks for posting the manual link Coopec, but the 1st is the parts manual which I've got, and the other's for a different engine, but on page 7 of the parts manual, it 'sort of' shows the issue.

Then identify which is which in the way I suggest. Be sure to turn the engine in its normal running direction

 

[RichardS]

In the manual that I have, which is more an owner maintenance item, the clearances (0.15mm) are given but not the torque on the head nuts, these I've taken from my other engine's manual at 30 N.m.

30Nm seems to be very low torque for the head bolts on a diesel engine. Are you sure about this?

Maybe it's the engine torque?

Richard

 

[jamie N]

Interesting engine. The engine was reassembled with a brand new head gasket, and new piston rings. What could possibly go wrong? The engine wouldn't fire; I knew that it was getting air and the injector was doing what it should, so it must've been the compression that was down. I'd really been fastidious about having the head and cylinder surfaces flat and prepared perfectly, so it was a bit of a mystery until I'd taken a glass of wine. The glass of wine helped to look at it from another angle of what else could it possibly be to affect compression; maybe the decompressor? A light bulb moment! The decompressor is fitted to the rocker box cover, on which the original gasket had been removed in pieces as it was destroyed, so I'd replaced it with silicone from a tube, a basic gasket sealant. This meant that the rocker box cover was now about 1-2mm lower than with a gasket, which just applied pressure to the inlet valve, so that when the engine was turned over, there wasn't enough compression, and there was a little 'blow-back' through the air inlet. I loosened the rocker cover, and the engine started on the key.
A quick trip to the motor factor, a few sheets of oil resistant paper later and some 'pretty cutting' with scissors to get 2-3mm of a seal, and it's back to the wine shop for a bottle of celebration.?

 

[jamie N]

The engine was finally fully fitted into the boat a couple of days ago, lots of hassle aligning it, and setting it onto the new engine beds, and so on. Had to renew the 'loom' to the engine panel that came with the engine, a new oil pressure sensor and gauge as well as a new alternator and S/S exhaust elbow. Connecting it up was fun as the controls, coolant and fuels fittings were all on the 'other' side from the previous engine, thus everything needed repositioning. So for the moment of truth, and it started on the button with everything functioning.
Total cost including the engine is about £300 quid. Gotta be happy with that, and having the time to be able to 'waste' on it.

 

[fredrussell]

Good for you! Always a worrying moment starting an engine for the first time after a rebuild.

 

[bikedaft]

The engine was finally fully fitted into the boat a couple of days ago, lots of hassle aligning it, and setting it onto the new engine beds, and so on. Had to renew the 'loom' to the engine panel that came with the engine, a new oil pressure sensor and gauge as well as a new alternator and S/S exhaust elbow. Connecting it up was fun as the controls, coolant and fuels fittings were all on the 'other' side from the previous engine, thus everything needed repositioning. So for the moment of truth, and it started on the button with everything functioning.
Total cost including the engine is about £300 quid. Gotta be happy with that, and having the time to be able to 'waste' on it.

magic well done for persevering. and you'll know how to do it all the next time... ;-) (hopefully never!)