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lost plastic piece inside coolant hole

1346 Views 24 Replies 9 Participants Last post by  Bastognekoek
I took the hard water pipes off the engine to swap them for a new ones. As the holes were dirty I decided to clean them. So I used a round brush that had a small soft plastic tip on it and attached it to a drill. Then all of a sudden I noticed the plastic tip was missing🤦‍♂️. See pics below.

Now I'm not sure if it is there. It might have flew off when I took the brush out of the holes while they where rotating.

The hole on the left leads to the waterpump and I can't see anything there, so I don't think it went that way. The other hole leads to the thermostat (among other things probably). I've looked from every angle I could but don't see it. Als using my finger I can't feel it.

So, what should I do?

Br. Diego

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No good answer here ... those coolant passages look big enough to allow the cap in; although relative size is difficult to judge from pics.

OP, you'll need to make your own judgment call on how much to keep looking vs when to button it up and see what happens.
Well the looking part is over now. I've put the whole cooling system back together (replaced everything). Just waiting on the o-ring of the coolant temperature sensor. After that I will do a pressure test. I've cleaned the boring holes of the hard pipes, but they still had some staining on there (felt ok though) so I want to make sure they don't leak.
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I'd Just leave it if you cant find it.The entire backing plate of my graf metal impeller pump got pumped into my cylinder head, i found maybe 20% of it but the rest of it is in there somewhere. Never affected anything.
This gave me some peace of mind until I remembered my new waterpump is a Graf with a metal impeller 😅
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This gave me some peace of mind until I remembered my new waterpump is a Graf with a metal impeller 😅
Its a good pump if your not using the car for motorsports, I have the graf pump in my daily.
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I would call it a day. Those plastic caps are probably the cheapest material the chinese manufacturer of that brush could find, aka it will either melt, disintegrate or get torn up by the churn of the pump impeller in no time.
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So, the little kitty is purring again:). So far, so good. No overheating. I’m amazed how silent the engine is now. No oil and no coolant leaks. Also no more dips in the idle when arriving at a stoplight. Not sure what that was, but I’ve also put a new MAF in and cleaned the ICV, so probably one of those two.

I’ll keep an eye on the temperature for a while. But for now it seems ok.

I have another problem. I hear a thumb when releasing the throttle. Not sure what that is, it sounds it’s coming from the back, but it might be the engine mounts. So off I go to the next repair.

Thx for your help on this one!
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