Gudgeon pins

[mojobaby]

I'm sure that this topic has been discussed before, but I can only find a 2008 thread.

Harbourseal has sent me a connecting rod and gudgeon pin, as my one is damaged, and I need to fit it to my piston.
The pin is obviously larger than the hole on the con rod, and its been in the deep freeze for a day, but it still doesn't fit. I know that the con rod should be heated as well to expand, but how much heat is needed and what is the procedure to fit it.

Is my only alternative to find someone with a press?

 

[mr-reno-139]

Back a good few years when i was working at the rensdealers in 1980changing pistons and liners was far more common than just putting a new engine there was a special tool which screwed through the gudgeon pin and a special steel plate to support the piston correctly after heating the con rods the pin could be pushed through my hands and wood b precision correctly until it cool down andGripped
not sure whether they haynes manual mentions this it certainly is in the genuine renault manual i suspect the tool is still at the garage that i used to work at and sitting there Going rusty lol

 

[angel]

This is quite a delicate job. Have you already removed your old piston?

The gudgeon pin is an interference fit. The small end of the connecting rod should be heated, and then the gudgeon pin will slide freely through it. It is not as simple as it seems, though.
First of all, the piston must only be fitted one way round in relationship to the connecting rod. This is very important. Check the drawing to see what I mean. Make sure you mark it clearly, it's all too easy to fit the piston incorrectly.
Now it's time to fit the connecting rod to the piston. Stand the piston inverted on the bench, with the pin inserted in one side, clean and lightly lubricated. Have a blowtorch already lighted and supported so that you can hold the small end over the flame. The manual refers to a temperature of 250 deg.C maximum. 30-45 sec of heating is enough. Quickly move the connecting rod with one hand and center it between the gudgeon pin bores, while pushing the pin with the other hand through the connecting rod. It should be done quickly, as the pin absorbs heat from the connecting rod, expands and tightens in a few seconds. Also you must check at the same time that the connecting rod is centered between the two piston bores, and the gudgeon pin is also centered. This is not necessary to be dead accurate, just make sure that the gudgeon pin will not protrude through the piston. Bingo! You have finished!

Good luck!

 

[mojobaby]

Thanks Mr Reno, and Angel for all that information. If you read the following thread, you will see how I arrived at this point:-

http://www.renault4.co.uk/forum/threads/connecting-rod-bolts.7174/

It was all due to the adjusting handle on my new torque wrench not lining up with the scale on the side of the wrench. I was over-torquing by about 10foot/pounds. I also incorrectly dipped the big end bolts in oil before I inserted them. They should be put in dry. So perhaps add another 5foot/pounds there. The result was that I stripped the bolt threads.

My biggest fear was that the female thread on the connecting rod had also been stripped. That's the reason why Harbourseal sent me his old connecting rod-(just in case.)

However, my new set of very expensive big-end bolts arrived a few days ago and this morning I fitted them. The female threads on the connecting rod held up very well, so I think I had only damaged the bolt threads(thank goodness)

Your method is exactly that same as the Youtube videos that I've been watching. You have about 3 seconds!!

 

[angel]

That's good news, small engine R4 pistons are fragile, and it is better not to be removed when they are not to be renewed.