Timing Belt Replacement – MGF K-Series is knowledge base item is from Mark Jones. The MGF’s K-series engine uses a timing belt rather than a timing chain like the B-series engine. So the timing belt requires periodic replacement. Rover Group’s recommendation for the MGF was to replace the timing belt every 60 months (5 years) or 60,000 miles. For the TF it’s recommended every 48 months (4 years) or 60,000 miles. Most people don’t put a lot of miles on their F or TF during the course of the driving season. So, chances are you’ll reach the 4 or 5 year mark long before you’d get to 60,000 miles.
Timing Belt Replacement – MGF K-Series might seem daunting. The rear fender (wing) prevents you from seeing the front end of the K-series engine. But it’s really not that hard. The MGF/TF’s workshop manual gives an excellent step by step procedure for replacing the timing belt and the water pump. So I won’t repeat the procedure here. What I want to do is provide some tips. Things that I have learned that I hope will make it easier for you. The first time you replace the timing belt I’d allow a full afternoon. The next time will probably only take you 2-3 hours.
Click on any of the images below to see a full size, full resolution image.
What’s Involved #
A timing belt service involves:
- Camshaft timing belt
- Rear camshaft timing belt (VVC engines only)
- Timing belt tensioner
- Water pump
- Alternator belt
In my opinion, the alternator belt should be replaced every time you replace the timing belt. I’ve read on more than one occasion about the alternator belt failing. When if fails it also and destroys the timing belt at the same time. If this happens, it causes the valves to hit the pistons (interference engine).
Tools Needed #
There are some tools that you will need.
- Camshaft locking tool (18G1570)
- Crankshaft locking tool (18G1742), and a camshaft pulley holding tool
- A good selection of metric wrenches and sockets. You will find that ¼” drive sockets and different length extensions will come in very handy
- Two torque wrenches, one of which can be adjusted to give a torque from approximately 5 Nm to 30 Nm
- A bottle of anti-seize is a must. Anti-seize is going to become your best new friend. When it comes to working on the F/TF because there are many steel bolts in aluminium alloy parts
- A 2.5”x3” telescopic inspection mirror. Allows you to see the camshaft’s alignment marks, the belt tensioner’s alignment marks, and to see the bolts associated with the belt tensioner and timing belt cover.
Timing Belts/Tensioners – Getting The Right Ones #
There are two different timing belts, as well as belt tensioners used on the K-series engine. A 23mm timing belt and a manual belt tensioner is standard for 1995 through 1998. From mid-1999, the switch was made to a 26mm timing belt, and an automatic belt tensioner. The VVC engine always used the 23mm timing belt and manual tensioner.
The tensioners are not interchangeable. The location that the tensioner bolts on to the cylinder head is slightly different between a manual and auto tensioner. Just because you have a 1998 or earlier MGF doesn’t mean the engine still has a cylinder head with a manual tensioner. Due to the F’s head gasket/overheating issues, many early cars had their cylinder heads replaced with later auto tensioner version. So, it’s best to check which tensioner is on your F’s engine before placing a parts order.
Water Pump Replacement #
It may seem odd to replace the water pump at this time. I questioned the rationale behind replacing it myself.
However, “real world experience shows” that the water pump’s life on a car that is doing average annual mileage will need replacing at around 70 to 80,000 miles. But that cars doing much less mileage, and especially those where there are longer periods of inactivity, many start to see the pump weeping coolant from around 25 to 30,000 miles.” To me this means that the pump is certainly good for more than 5 years. But that it will start weeping before getting to the next timing belt change interval. The amount of work needed to change the water pump is considerable. It is best to always change it at the same time as the timing belt. Another good reason for replacing the water pump is that it forces you to change the coolant.
Process Tips and Suggestions #
Here’s where I’ll supplement the workshop manual process.
Engine Mount Bolts #
The two bolts used in the right hand engine mount may be difficult to remove. The bolts are on a slight outward angle and they are torqued to 155 Nm. The workshop manual says to remove and discard the bolts. This is probably due to the fact that the bolts have a thread lock patch on them. Also the bolt’s head may be damaged during the loosening and tightening process. I think it is a good idea to have spares on hand.
Unfortunately, this bolt (part# FC114167) has not been available from XPart in over a year. Fortunately, a replacement is available from Mike Satur (UK-source) and Belmetric. The Belmetric part number is BFD14X80YLW. If reusing the bolt, make sure to use a medium-strength thread lock compound.
Camshaft & Crank #
With the camshaft timing marks aligned, insert the camshaft locking tool. Next you have to remove the crank bolt. To get that nut off requires the use of the crankshaft locking tool in place of the starter motor to lock the flywheel before attempting to remove the bolt using a socket and breaker-bar or an impact wrench.
Taking the timing belt cover off the front of the engine is straight forward but there is one bolt that holds the cover on from the backside of the water pump; not the easiest to get to. I don’t bother re-installing this bolt.
Water Pump #
The water pump uses an O-ring type gasket. No sealant is necessary. I do suggest to use a couple of very small dabs of silicone to RTV to ensure that the gasket stays in its groove while maneuvering the pump up into its spot. There’s not enough room between the rear sub-frame and the inner wheel well to maneuver the pump and hold the gasket in place.
Timing Belt Install #
Installing a new timing belt can be performed by one person. However, trying to keep the belt on the different pulleys as you work your way around to the water pump can be challenging. A tip I learned from Roger Parker is to wedge a boxed-end wrench in the space between belt and the oil pump’s casting belt guide to hold the belt on the crankshaft gear. A couple of clothes pins between belt and the oil pump’s casting as worked very well.
Another tip provided to me by Roger Parker that I have used with success: When looking at the crankshaft gear there are two timing dots stamped into the front face of the gear. These marks are aligned with a cast-in line on the oil pump body. The idea is position the dots one either side of the line. Roger suggests moving the crank back (anticlockwise as you look at the crank) half a tooth. As the belt is fitted between the crank and exhaust camwheel, the belt easily slots into engagement. When the slack is taken out the correct timing is achieved. Only half a tooth: no more or you will end up one tooth out the other way!
To install the belt, start by just putting the edge of the belt on the edge of the crankshaft pulley and then put the edge of the belt onto the camshaft pulleys, ensuring that the belt is as tight as possible between the crankshaft gear and the camshaft pulleys. Then feed the belt around the tensioner and then the water pump. Once the belt is on the leading edge of each gear and the tensioner,push it inward until the belt is flush with the front ends of each gear and tensioner. A trick for the manual tensioner, is to leave the manual tensioner very loose on its mounting bolt, which makes it easier to initially fit the belt to the tensioner and the water pump.
Once you have tensioned the belt as per the manual, rotate the crankshaft twice and recheck the tension and the alignment of the camshaft marks and the crankshaft marks. If the timing is off, the crankshaft and camshaft timing marks do not align; the crankshaft timing mark will be forward of the alignment mark on the oil pump and/or the camshaft marks won’t align.
If the crankshaft alignment it off, it can be corrected. Rotate the camshafts (with the belt still on) until the camshaft locking tool can be reinserted. Take the belt off and rotate the crankshaft backwards until the dots on the crank gear are aligned with the cast-in line on the oil pump. NOTE: the K-series is an interference engine: don’t be turning the crank a revolution in order to align the marks.
If the timing of the camshafts are off, you will have to use a camshaft pulley holding tool to rotate the camshafts one at a time until the marks on the pulleys align, reinsert the camshaft locking tool and reinstall the timing belt. This is a bit fiddley because the cams are on the lobes when the marks are aligned, so they tend to want to move.
If all the timing marks are aligned properly, install the lower timing belt cover. Torque the crank bolt to 205 Nm. Reinstall the starter, and the upper timing belts cover. Your timing Belt Replacement – MGF K-Series is now complete.
Closing Thoughts #
At this point, install a new alternator belt. If you happen to have a/c, I’d suggestion inspecting the tensioner pulley, make sure that bearings are not worn out. If sound like a bag of rocks, replace it.
That’s it, get out and enjoy your F/TF for another 5 years.
Other Materials #
I’ve built this website and spent time on the knowledge base to bring together a lot of information I have collected from around the internet. The intent is making it easy to find rather than having to know about and have skills with search engine query terms to get what you were looking for. Please make use of the knowledge base.
