Another timing belt thread

[mutley]

Hi All,

I've decided that I have tempted fate far too long, have driven my car literally all over the UK (and still using as a daily driver, kept outside) and now sitting on 114k miles, that I will bite the bullet and take the car into HUK for timing belt change.

My question is what else should I get done at the same time, I know apart from the belt, there is the water pump and tensioner, but can anyone think of anything else?

Ta

Jim

[Hagasan]

Hi Jim,

I've read that the harmonic damper/pulley is another part worth changing as it can seperate from the actual pulley.

Kaz recently wrote this up in his health check posts and I know Martin, MART155 had this very issue earlier this year. It can wreck the engine if it fails as I think it can take the cam belt with it.

The damper was one of the parts, along with the pump(including belt cover), tensioner and belts that I pick up when in the US for my next service...

Gary

[mutley]

ahh yeah, forgot about that thing, I'll probably speak to the garage and see what they recommend, then I'll speak to Kaz ( I trust him more than HUK).

Cheers
Jim

[AR]

Check and adjust valve clearances, new camplugs, maybe new valve cover gaskets.

They will probably do a coolant flush as well since doing the water pump.

Cheers,

AR

[Ciaran]

I know Mark J in Dali has a mixed fan base on here, but he has a very good 100,000 mile service pack. It is a very good and comprehensive starting point...

[amo]

I know Mark J in Dali has a mixed fan base on here, but he has a very good 100,000 mile service pack. It is a very good and comprehensive starting point...

mmmmmmm mixed fan base personally i think hes ok as i nearlly got away with 2.5k of mine
but hay
up to you
thx amo

[mart155]

Hi Jim,
As Gary said above, I would seriously consider changing the crank pulley at the same time as the cambelt. I was very lucky that it didn't wreck the engine when mine went.
If you speak to Kaz, I am certain he wil agree. He might even be able to get one for you cheaper than the £330 + vat that HUK will charge.
Martin.

[duncan]

The drain hole on the water pump bearing changed position slightly between the earlier and later cars, the OE Honda pump that is currently available is the later version. You will need either a different timing belt cover or to effect some magic with a length of plastic tubing, otherwise any coolant seepage from the bearing will drip onto the belt.

[Hagasan]

The drain hole on the water pump bearing changed position slightly between the earlier and later cars, the OE Honda pump that is currently available is the later version. You will need either a different timing belt cover or to effect some magic with a length of plastic tubing, otherwise any coolant seepage from the bearing will drip onto the belt.

The new belt cover should come as part of the updated water pump "package"

[mutley]

My train of thought so far is first I'll go speak to the garage, find out all the costs of parts, labour etc, then see if they will be happy with me supplying the parts (Genuine Honda parts) and then take it from there.

If they are happy for me to supply the parts, then I'll shop about and see what I can get cheaper than the usual HUK rip-off.

Cheers
Jim

[Kaz-kzukNA1]

The drain hole on the water pump bearing changed position slightly between the earlier and later cars, the OE Honda pump that is currently available is the later version. You will need either a different timing belt cover or to effect some magic with a length of plastic tubing, otherwise any coolant seepage from the bearing will drip onto the belt.


The new belt cover should come as part of the updated water pump "package"

For early models, you can no longer order the water pump or the lower cover separately. Even if you just want to have the lower cover, it will come with the water pump.
So, if you order the parts by yourself using the old part no for the water pump and for the lower cover, you will end up with 2 complete set of these if your parts coordinator didn't notice it.

However, for the later models, you need to order the water pump and the lower cover separately, if I remember correctly.

So, it is best to check based on your VIN as the concept of 'Year model' is different between each country.


Hi, Jim.

While every car manufacture specifies the service schedule based on the mileage and age, I personally believe that the service should be tailored for each NSX as our cars are getting very old and some of them are at high mileage or being used at the circuit. We need to take into consideration the driving conditions and owner’s demands.

For timing belt service, followings are just my personal recommendation.
For those who are interested in the same service, please note that this is for NA1 MT early model so it could be different from yours.

0. Pre-service
* Compression, leak down and engine block leak test:
After long years and possibly lots of mileage, it is time to check the condition of your engine. You are very likely to adjust the valve clearance so it is best to check the compression before and after the timing belt service. You may want to carry out the leak down check if you have never carried it out before.
Although the engine head is quite strong on our engine, it would be a goof idea to carry out the block leak test as well.

1. You should replace/adjust;
* Timing belt: Obviously.
* Crank Pulley: Essential. As you know, the weight balancer could split.
* Valve clearance: Essential
* A/C & ACG Belts: Makes sense to replace them at the same time.
* Water pump & Lower cover: As mentioned above, for early model, these will come as a set. However, this is not the case for the later model.
* Timing belt Tensioner & spring: The Tensioner has bearings inside so replace it with the spring.
* Gasket set, Head cover: Essential. Famous for oil leakage. You’ll need 2 set of these. These will include not just the rubber sealing for the head cover, but also the rubber washer under the cap nut and the rubber seal for the spark plug hole.
* Sealing for Rear and Front IGN Coil cover: Replace them and apply small amount of silicone grease to keep them soft. Over the time, these can get harder and eventually, water can get into the IGN Coil hole resulting in corrosion at the IGN Coil or Spark Plug body.
* Camshaft Oil seal: Essential.
* Camshaft end cap: Essential. Famous for oil leakage
* Spool valve filter and O-ring: Famous for oil leakage
* Oil Pan gasket: Essential. The specified torque figure for the nuts in the workshop manual is questionable so be careful not to over tighten them resulting in repeated oil leakage.

2. You may want to consider replacing;
* Header Tank & the cap: Makes sense to replace them with the water pump.
* Coolant Hoses: 23 of them for early MT models.: Makes sense to replace them with the water pump. Also, you will loosen the three bolts holding the oil cooler that has two most time consuming coolant hoses so best to replace them at the same time.
* Thermostat

* Inspect IGN Coil: Water can get inside the coil assy hole while washing your car or when it’s raining.
* Spark Plug: Get OEM one. Good balance between cost/performance/durability.

* Oil Pump: I prefer replacing this but depends on your mileage and driving conditions.

* Lost Motion Assy: On early models, quite often, you can’t get rid of mechanical noise by just adjusting the valve clearance. It is very likely that your Lost Motion Assy is getting tired and lost its springiness. Best to replace them while you are carrying out some work inside the engine but you may struggle replacing this with the engine inside the chassis.
Last year, Honda finally made the modification to this part as some of us were worried about sharing the same part between later and early engine head. The length was different between the two yet the same part was shared. Now, it has been addressed.
* O-ring – Rocker shaft Oil control Orifice: You will need to replace these any way if you are replacing the Lost Motion Assy. You may struggle to replace these if you keep the engine inside the chassis.

* Oil pressure sender unit: If your oil pressure gauge is showing almost 0 on idle (quite common on very early model), it is best to replace this as access to this unit is quite limited.

* Fuel Pressure regulator: Piece of mind.
* TDC sensor: The potting glue will melt and make the area dirty. Even the new one will do the same so may be not required.
* A/C idler pulley: It may get noisy after many years.
* Seals, timing belt covers: Ideally, not just the seals attached to the black plastic covers but also the ones attached to the silver metal covers under the plastic ones.
* Eng/Trans mount: By now, all four will have lots of tiny crack especially the ones at the Front and at the rear.

Regards,
Kaz

[mutley]

WOW,

Thanks Kaz, you have now given me a hell of a lot to think about, as you know my car inside and out (quite literally) you know that everything you have mentioned above will need done.

As for prices from HUK for all these parts and then the labour I can see this being quite costly, so I may postpone from next month until I can see if I can source these parts.

Cheers
Jim

[goldnsx]

The long list contains some positions I'd regard as 'throwing parts at the car' or completely overservicing.
- why a cylinder leakage test if the engine runs fine?
- why a new pulley? You can install the shield and wait until it separats.
- why spark-plugs? They're due every 100k km.
- why oil pump? It's a Honda, it doesn't need replacement.
- A/C idler, engine mounts, oil sender unit and fuel presure regulator have nothing to do with a TB job and can simply change if it NEEDS replacing.
- the tensioner spring needs not replacing. The bearing does.
- all TDC sensors are leaking to some extend. It's not necessary to change them. Ask LarryB on prime who has done dozens of TB jobs, he'll confirm that.

If the car is younger or 02+ it only needs the basic parts and NO cam plugs, LMA and so on. This can be done next time. Cam plugs don't start leaking before 10 years, nor do LMA's go bad before 100k km, generally. The LMA's are a point to look at on the older cars.

[mutley]

The long list contains some positions I'd regard as 'throwing parts at the car' or completely overservicing.
- why a cylinder leakage test if the engine runs fine?
- why a new pulley? You can install the shield and wait until it separats.
- why spark-plugs? They're due every 100k km.
- why oil pump? It's a Honda, it doesn't need replacement.
- A/C idler, engine mounts, oil sender unit and fuel presure regulator have nothing to do with a TB job and can simply change if it NEEDS replacing.
- the tensioner spring needs not replacing. The bearing does.
- all TDC sensors are leaking to some extend. It's not necessary to change them. Ask LarryB on prime who has done dozens of TB jobs, he'll confirm that.

If the car is younger or 02+ it only needs the basic parts and NO cam plugs, LMA and so on. This can be done next time. Cam plugs don't start leaking before 10 years, nor do LMA's go bad before 100k km, generally. The LMA's are a point to look at on the older cars.

I can see where you are coming from, but my car is a 1992, with 114,000 miles on it, and has been treated pretty rough by previous owners, so if doing little jobs that may not be necessary but desirable, then it can only prolong the life of the car/engine.

Jim

[AR]

Cam plugs don't start leaking before 10 years

Back in 2005 my MY99 camplugs were leaking.

[goldnsx]

Back in 2005 my MY99 camplugs were leaking.

Leaking or sweating? :) Are you sure it has been the camplugs? The edges of the cylinder head cover gasket are prone to leak and they're in a distance of 5 mm to the plugs.

@mutley: I agree with you that - regarding the age of the car - more things have to be done than on a 92.

I've changed my philosophy on changing parts the way that I don't change every parts that could be fail in 2, 3 or whatever years if it can be done in under 10 minutes then. ;)

[NSXGB]

Back in 2005 my MY99 camplugs were leaking.


I fitted the SOS replacement cam plugs that don't leak........they did after 2 years.....:rolleyes:

[AR]

Leaking or sweating? :) Are you sure it has been the camplugs? The edges of the cylinder head cover gasket are prone to leak and they're in a distance of 5 mm to the plugs.

@mutley: I agree with you that - regarding the age of the car - more things have to be done than on a 92.

I've changed my philosophy on changing parts the way that I don't change every parts that could be fail in 2, 3 or whatever years if it can be done in under 10 minutes then. ;)

Sure 100% same with my NSX-R and my MY93, the actual camplugs were quite "brittle".

[goldnsx]

Maybe it's a confusion of the used terminology. I regard leaking as oil draining from them in a higher amount while sweating means oil/dirt stains with no loss of oil.