Honda crv 07. remove bolt from snapped oil sensor

[Jonny Vee]

You’ll soon find out if the original thread is intact, just drill very very carefully keeping it square.

Finger crossed mate. I really need to get car working again.

 

[Jonny Vee]

While waiting for the tap and drill to arrive, is there any kind of guide which would help to make drill going straight? I know it trick and there is no much surface flat for anything but you never know if someone had any similar experience before

 

[Old Salt]

You need to make sure you can hold the drill square so will your drill physically fit in the space available?

Probably some sort of brace that you can line up on. Maybe a wooden frame that you can rest an arm on to help take the strain. But really its just a knack in drilling straight.

You could start with opening it out in easy stages but bear in mind that all the drill bits will follow the same path of the first drill. It is possible to re centre a drill but I dont think that will be possible in these circumstances.

I would use the smallest diameter drill possible to take some material out and then just gradually enlarge it until just before you hit the bottom of the screw threads. Then try tapping the new thread in the hole. With luck the thread will collapse or release as you get closer to the size required.

Use sufficient grease to try to catch any swarf before it falls inside, if necessary stop and remove the swarf and apply clean grease. Do the same when using the tap. Take it easy when tapping half a turn and a quarter turnback once you get started. If using a taper tap you may need to do a couple of turns to get it going.

With any luck the old sensor thread will be easily removed once you have weakened it and a quick clean up of the thread should see you fitting the new sensor.

If its been butchered in the past you will need to either fit a helicoil or you could drill it larger and fit some form of adaptor but we can cross that bridge when we come to it.

 

[Jonny Vee]

Removed the bolt from the block. First 4/5mm of thread are damaged. Not sure if I have damaged or were already damaged. The switch still seem to screw in well for the remaining thread and want have a go. I guess its screw fine for another good 5mm. i will start putting back radiator and everything leaving the switch as last thing. load of metal cut, hope I managed to get it out with hoover and grease while drilling.

What the best way to flush the area. Do I have to turn engine on? For a long and if to idle or accelerate?

Do I have to change the oil and filter on the engine too?

When getting to a point of putting switch on. I have these as per link below. Can I use it and what about the external bit whee thread is gone? A bit of Teflon tape?

sealent https://www.amazon.co.uk/gp/product/B01B9P3P7Y/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1

Many Thanks

 

[Old Salt]

Congratulations I bet that’s a relief. We will all have our own goto sealants. Personally I would use a couple of wraps of ptfe tape and some heldtite.
https://www.northerntankstore.co.uk...MI4be3-qHF9AIVDO7tCh0OXQSKEAQYAyABEgJezvD_BwE

I used to use this on HP steam systems, salt water, oil and fuel pipe joins. Works well but easy to remove if required.

As regards flushing it wouldn't hurt to give it a spin over. I would be inclined to have a good look to see if anything is visible in the hole, remove the plug leads so it wont start, place a rag over the hole and turn it over. You can then either give it an oil change and new filter or run it a bit at idle, then round the block before draining the oil and changing the filter.

It is always going to be a risk whether any debris has managed to fall in but at some stage you need to bite the bullet and give it a go.

 

[Jonny Vee]

Congratulations I bet that’s a relief. We will all have our own goto sealants. Personally I would use a couple of wraps of ptfe tape and some heldtite.
https://www.northerntankstore.co.uk...MI4be3-qHF9AIVDO7tCh0OXQSKEAQYAyABEgJezvD_BwE

I used to use this on HP steam systems, salt water, oil and fuel pipe joins. Works well but easy to remove if required.

As regards flushing it wouldn't hurt to give it a spin over. I would be inclined to have a good look to see if anything is visible in the hole, remove the plug leads so it wont start, place a rag over the hole and turn it over. You can then either give it an oil change and new filter or run it a bit at idle, then round the block before draining the oil and changing the filter.

It is always going to be a risk whether any debris has managed to fall in but at some stage you need to bite the bullet and give it a go.

Heldite look good but not immediately available. Is there any other suitable option which could do the work?

What about this one from Screwfix? https://www.screwfix.com/p/fernox-hawk-white-jointing-compound-400g/69694

It`s a Diesel engine. What I can disconnect to avoid it starting?

 

[Old Salt]

Lots of other places will sell the heldite jointing compound its definitely on ebay.

To stop it starting you can just pull the fuel pump fuse, injection fuse or the fuel pump relay.

There are clips on youtube to show where they are located.

 

[Harry Bloomfield]

Sorry, I've a been a bit busy today, helping a friend sort their car issues out, on my drive - still defrosting from the experienced, but well done..

My own thoughts on trying to ensure there are no bits of metal fragments in the gallery, are to simply run the engine for as brief a time as possible, but long enough to blow a reasonable amount of oil out. Basically it should be not much longer than the time you normally need to crank it over to start it, then off. All done before the sensor is reinstalled, with the area cleaned and with a clean bit of rag over the sensor socket to catch what ever is blown out. You need two people to do that, one to crank it over, the other holding the clean rag in place. There might be a fair bit of pressure, 50 to 80 psi so anticipate that, who ever holds the rag.

You can then check the rag to see what if anything has been blown out, not that it will tell you much either way. I would then install the sensor, drain the oil and refill. Maybe only bother changing the filter if it is about due, because your existing filter will certainly catch any swarf still left in there - besides, you have been working on the filtered side of the oil system anyway.

Hopefully, the gamble will have paid off for you. Good luck.

 

[Jonny Vee]

Sorry, I've a been a bit busy today, helping a friend sort their car issues out, on my drive - still defrosting from the experienced, but well done..

My own thoughts on trying to ensure there are no bits of metal fragments in the gallery, are to simply run the engine for as brief a time as possible, but long enough to blow a reasonable amount of oil out. Basically it should be not much longer than the time you normally need to crank it over to start it, then off. All done before the sensor is reinstalled, with the area cleaned and with a clean bit of rag over the sensor socket to catch what ever is blown out. You need two people to do that, one to crank it over, the other holding the clean rag in place. There might be a fair bit of pressure, 50 to 80 psi so anticipate that, who ever holds the rag.

You can then check the rag to see what if anything has been blown out, not that it will tell you much either way. I would then install the sensor, drain the oil and refill. Maybe only bother changing the filter if it is about due, because your existing filter will certainly catch any swarf still left in there - besides, you have been working on the filtered side of the oil system anyway.

Hopefully, the gamble will have paid off for you. Good luck.

Harry, Thanks for your input too.

Heldelite has been ordered with fast delivery.

Slightly difference between you and Old Salt is the way to flush the gallery. Old salt suggest to idle and run around block before changing oil. You suggest to change without starting engine.

I know everyone will get a different opinion. I will try to get a good chunk of oil out hopefully if anything left will comes out and then put rag to clean. I have been using hoover too, hopefully has managed to get swarf out.


How long I need to wait for the Heldelite to settle before starting engine?

 

[freddiemercurystwin]

So no expert here but I'd think a quick turnover as per Harry's post would be adequate.

 

[Old Salt]

How long I need to wait for the Heldelite to settle before starting engine?

Preferably overnight, at least a couple of hours, especially in low temperatures, but it is good stuff. And the best bit is it cleans up easily if you do need to try something else.

Toss a coin on whether to run the car before changing the oil, my thoughts are to circulate the old oil along with any missed swarf, caught by the old filter then drain and a new filter for a fresh start.

lots to be said for blowing out some oil then an oil change, your call really, no right or wrong way in this situation.

To do the job properly the engine should have been out, sump should have been removed, block should be stripped, internal clean, reassemble to be certain no swarf has been left behind. But thats another story.

Good luck

 

[freddiemercurystwin]

Toss a coin on whether to run the car before changing the oil, my thoughts are to circulate the old oil along with any missed swarf, caught by the old filter then drain and a new filter for a fresh start.

So after the oil pressure sensor does the oil then travel to the filter or the bearings first?

 

[Old Salt]

I would have to look at the engine design/diagram/cut away drawing.

Logic would say, sump, pump, filter, sensor, bearings but if any swarf has dropped inside and doesn't come out when its turned over (which is what I suggested before a run round the block) it will be circulated until it either gets trapped somewhere, drops back into the sump or gets caught by the filter. Hence why I suggested a run before changing the oil and filter.

There is no right or wrong way in these circumstances, just taking whatever precautions you can and trying to prevent any future problems.

 

[Harry Bloomfield]

I would have to look at the engine design/diagram/cut away drawing.

Logic would say, sump, pump, filter, sensor, bearings but if any swarf has dropped inside and doesn't come out when its turned over (which is what I suggested before a run round the block) it will be circulated until it either gets trapped somewhere, drops back into the sump or gets caught by the filter. Hence why I suggested a run before changing the oil and filter.

As I suggested, the oil pressure switch is after the pump and filter, the only route back from the pressure sensor is via bearings - which is why others have raised their concerns about the potential for serious damage. The swarf cannot makes it's way to the sump by any other route. My hope is that the oil gallery route from the sensor goes up, so that any swarf will drop towards the sensor hole and thus be quickly flushed out by oil pressure, if the sensor is left out.

I would also be very wary of how long you turn the engine over for, without the sensor in place, because there will be almost no oil pressure to lubricate the bearings in the engine, so damage can quickly result. It only needs to be cranked over for long enough to try to flush swarf out of the oil gallery, by oil pressure.

So after the oil pressure sensor does the oil then travel to the filter or the bearings first?

I would hazard a guess at the sensor's oil gallery being the end of the line, not going anywhere else, but as OS suggests - to be sure we would need to have access the engine diagrams.

 

[Mottie]

You will catch zero swarf in the filter. It's the wrong side of the filter. Personally I wouldn't use any sealant on the switch either - one piece of that in the gallery and you'll suffer the same damage to bearings if it blocks the oil way to the crank.