Interested to hear what anyone else has on this topic but just to be clear I bought a bunch of solid silicon grommets that were designed to replace the existing rubber seals that you find enclosing the ink posts in a Canon iP4200/MP500 printhead.

I got quite a few of these but also received a single set of the thinner grommets which instead of replacing the existing rubber ones, you just slide these on top.


To date the "replacement" grommets actually seem to create a pretty good seal around the ink post BUT it seems that they aren't entirely leak proof as there's every indication that after a few lines of colour (usually after a cleaning routine) the ink fades out and you find air (or nothing) is being "printed" instead of actual ink which would indicate a leak somewhere.. Believe me I checked everything on the 4 sets of CIS kits I've created and in all bar one instance there were no other reasons for the leak.

As near as I can tell, the reason for this is that the grommets are actually a little too thick and the cartridge push down and stretch the grommet (elongating it).. This creates an uneven pressure that causes a tiny gap in the base of the grommet where there's a small circular raised area. This doesn't happen with all the grommets but I've noticed that the Yellow ink suffers from this in particular and this may well be due to its position in the middle of the carriage and any pressure exerted (or not) by the printhead lever, may be a partial explanation for this.. Not entirely sure at this point.

Based on my other experiences I suspect the best approach is to use thin silicon grommets placed on the original rubber grommet rather than using the "replacement" silicon versions.

Slightly telling is the fact that the manufacturers have stopped supplying the "replacement" grommets now and only provide the thin ones but if you're hitting problems with your kit and have the older part I would recommend requesting replacements to see if that solves your problem.



Anyway, has anyone else seen this sort of problem and/or got any suggestions as to what else could be going on... ?


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Printers: (Canon) MP500/830, MX700, iP4000/4200/4300/4500/5200, iX4000(A3) (Epson) C84/86, D88, CX6600, R285/800/1900 (HP) K550, K850, K5400, L7680

An additional problem that I've found recently is that in some instances a thicker grommet can result in the cartridge foam and the ink receiver in the printhead being forced apart enough that ink flow is impeded or essentially redirected into the space around the ink receiver instead of into the port itself.

To counter this problem you may need to place a small wedge between the cartridge and printhead retaining lever to force the cartridge down a little further and ensure proper contact between port and cartridge foam.

Obviously this issue would only affect a sponged cartridge and is only a known issue when using Canon OEM cartridges as part of the CIS.


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Printers: (Canon) MP500/830, MX700, iP4000/4200/4300/4500/5200, iX4000(A3) (Epson) C84/86, D88, CX6600, R285/800/1900 (HP) K550, K850, K5400, L7680