740 760 hints & tips
In this section I’ll give you some hints and tips to get more out of your Volvo 740, 760 or 780. It includes saving fuel, improvements and modifications for your Volvo 740 or 760, preventing high costs, the right preventive maintenance and several other useful tips to enjoy your Volvo 700-series car for a long time!
Improving the fuel economy of your Volvo 740, 760 or 780
A Volvo 740, 760 or 780 isn’t a very economical car: they’re pretty heavy and their aerodynamics aren’t the best. The D24 diesels are pretty economical (their consumption is about 1 litre per 14 kilometers (almost one mile per litre), which isn’t bad for an old diesel: a Volvo V70 TDI or 850 TDI with a much newer engine uses the same amount of diesel! That’s why I’ll focus on the petrol engines since they can be improved a little bit.
To improve the fuel economy of your Volvo 700-series car, try to comply with the following recommendations:
- Replace air filter, fuel filters, spark plugs (I recommend to use the OEM spark plug set) and its cable set, ignition parts (like distributor cap and rotor) to be sure the ignition, fuel and air mixture are in its best condition. Always replace them on time (with the right service interval)!
- Adjust the valves of your car on time, check them at least every year.
- In case of a carburator: be sure it’s adjusted well. A carburator which is maladjusted consumes a lot of fuel!
- Be sure the engine has the right oil (use premium oils like Castrol, Mobil or Shell Helix, not cheap garbage which don’t cool down or clean the engine at all) and change it on time. Change the oil filter at eats oil change. Volvotips recommends the OEM Volvo filter, or a Mann filter (which is actually the OEM filter).
- Clean the throttle body every year, and clean it when you just bought the car.
- A Volvo 740, 760 or 780 isn’t a very aerodynamic car, they’ll use a lot of more fuel when driving harder than 110km/h (69mph). The optimal fuel consumption of a Volvo 700-series car is between 90km/h and 110km/h (56mph-69mph), because the automatic transmission will use its lockup torque converter at 90km/h or higher. A manual transmission should be in fifth gear (or use the overdrive, in case of a M46 gearbox) when driving 70km/h (44mph) or harder. In most cases you can use the fifth gear already just above the 60km/h (38mph). The driving style is the most crucial factor for your Volvo 740, 760 or 780’s fuel consumption. Try to keep the tachometer under the 3.000rpm at all times.
- Replace the oil of the rear axle if you’re not sure when it’s done for the last time. It’s an item most people forget and doesn’t replace.
- The tire pressure should be a bit higher than Volvo recommends. The pressure of 1.9 bar / 28psi (2.1 bar / 30 psi for the late 700-series) is recommended by Volvo to make sure the car is very comfortable, but it’s way too low actually. I recommend to use 2.3 bar / 34psi, it saves a lot of fuel compared with the 1.9 bar Volvo recommends, but you’ll keep enough grip and comfort.
Useful supplies for your Volvo 740, 760 or 780
Some simple tools, solutions and lubrication will help your Volvo 700-series car to stay in its best condition and survive the winter.
Spray lube and protecting rubbers
Many people are using WD40 for the doors, hinges, pivots, screws, nuts, and cables of their Volvo 740. WD40 isn’t bad at all, but there are much better sprays with much better results. For penetrating oil use PBblaster or try Castrol DWF. As lubricating oil I would suggest Valvoline Pyroil, Super Lube, Kroon, Valma or any other silicone spray. When winter is coming you should lubricate all door hinges, door locks, trunk, sunroof mechanism and mechanism of the hood (otherwise it will be iced up if you want to open it when having a breakdown). Don’t forget to grease all door seal rubbers, trunk rubber and sunroof rubber (you don’t use it during the winter, but not greasing it will damage the rubber) with a good rubber grease like 3M silicone grease, 303 silicone spray, Autoglym Vinyl & Rubber care, Valma Rubberstick or Vinylex . Don’t use Vasoline since it’s petrolium-based and will deteriorate rubber.
Some of the cleaning and care products I use: Protech odor neutralizer, Turtle Wax leather care (when I have a Volvo with leather upholstery), Teroson cavity spray (to protect doors and sills from the inside against rust), Motip PTFE teflon spray for lubrication and an interior cleaner of Turtle Wax
The Volvo 700-series have some issues with electronics over the years. In most cases it’s caused by contacts becoming oxidized or the ground is bad. To fix the ground in most cases sanding will help, but for oxidation contact spray could help. For electric there are many types of contact cleaners. One of the best is Caig’s DeoxIT. But if you’re using contact cleaner it’s not sure the problems of your Volvo 740, 760 or 780 will be solved: it’s a temporary solution and dust will stick into the cleaner. If you’re using contact spray: make sure you’re using an anti-oxidation compound as well, like GB’s OxGard (recommended for plugs and connectors).
Cleaning the upholstery and interior of your Volvo
Protecting the upholstery and interior against UV radiation and wear is very important if you want to keep your Volvo 740, 760 or 780 in its best condition. For the fabric upholstery you could use 303 High Tech Fabric Guard or Protech upholstery cleaner. For vinyl and leather there are several products: the Turtle Wax leather cleaner is pretty nice, just like Poorboy’s Leather Stuff. Protecting your dashboard, door panels and other plastic parts Meguiars Ultimate Protectant is very good. There are many different brands and you’ll find many discussions on the internet which brand is the best, but in my opinion Meguiars, Poorboy’s, 303 and Autoglym are very good. I usually buy Protech. Talking about Protech: if the previous owner used to smoke in the car (or had a dog in it, or he smells terrible himself), try Protech Odor Neutralizer. It’s pretty expensive, but in my opinion it’s the best way to get rid of nasty odor like tobacco smell.
Tools for your Volvo 700-series car
The Volvo 700 doesn’t need any special tools for the standard maintenance. Buy a nice socket set which includes a screw set to store in the car (be sure it’s metric, not inches). Very helpful when your car has a failure during a roadtrip. Also a set of spanners isn’t a bad idea.
The original Volvo jack in the trunk isn’t the best one: it’s not very handy to use and takes a lot of time before the car is coming up. I recommend to buy a hydraulic floor jack: it is cheap and works much better than the standard jack. And buy a cross wrench for your car: easier to use than the standard wrench.
Washing your Volvo 740, 760 or 780
Washing your car regularly will help against dirt accumulation and rust (if you have a pre-88 Volvo 740 or 760, or a 700-series car which is exposed to a lot of salt in the winter). The best way to wash your car is by hand, not in a car wash. A car wash doesn’t reach certain areas, like the inner side of the rear wheel arches. You should consider detailing your car, but most drivers don’t care about that. If you want to detail your car with products of Autoglym, Protech, Poorboy’s or Meguiars: there are a lot of forums and websites on the net about car detailing. Be sure the paint of your car is covered with a nice layer of wax: it protects your car (especially the non-metallic paint) for getting dull. For your windows I would suggest to use RainX, it really helps a lot during rainy seasons.
Preventive maintenance for your Volvo 740, 760 or 780
In this part I’ll show you some items you might replace or service when you just bought a car or has a high mileage. The weaknesses of the Volvo 740, 760 and 780 are described in the Volvo 700-series buyers guide I wrote earlier. You should check it out and check all weaknesses as described in that article.
Volvo 700-series overhaul
If you don’t have any service history of your (just bought) Volvo 700-series car, I recommend to replace all filters (oil filter, air filter, fuel filter etc), change the oil and new spark plugs to be sure they’re fresh. Check the condition ignition parts (coil, rotor, distributor cap and spark plug cables) and be sure the fuel pump is working fine. For injection engines: check the fuel pump relay and buy a spare relay to keep it in the glovebox: these relays often breaks! These relays aree not expensive and have Volvo part number 3523608 for the LH-Jetronic (white relay) and Volvo part number 3523639 in case of the K-Jetronic system (green relay).
Check the thickness of the brake pads and rotor. If there any doubts about the brake fluid: change it, just like the coolant of the car. If there is any play at the front wheels: it could be caused by worn ball joints or suspension bushings. Replacing them isn’t very difficult and pretty cheap, but be sure your car is aligned well (otherwise the car wouldn’t drive well and tires will be worn out soon).
If the splash plate underneath the car is gone or broken: buy a new one. They’re very easy to install, improves the airflow of the bottom of the car and prevents the engine getting dirty or wet.
Engine and gearbox mounts
If the engine is shaking a bit, it’s time to replace the engine mounts. The support rubber for the gearbox can also be worn. Especially the automatic gearboxes have worn support mounts because the ATF will deteriorate the rubber. When replacing the rubber mounts: check the condition of the universal joints of the drive shaft, bearing of the drive shaft and its support rubber.
Throttle body of the Volvo 700-series
As mentioned earlier in this article: it’s recommended to clean the throttle body of your Volvo 700-series car. In case of an automatic gearbox: check the color of the oil. The ATF should be bright red and smell a bit sweet. If it smells burnt or is dark: replace it as soon as possible! Check the flame trap and clean it if necessary.
Heater, vacuum and cooling issues
The heater control valve of the Volvo 700-series is also a weak point because it’s made of plastic. When it’s broken it could lead to severe damage (especially on the Turbo models). Check if the heater control valve is working fine and be sure the heater radiator isn’t leaking. If you’re checking the cooling: check the condition of all hoses and radiator, intercooler (in case of a Turbo Intercooler or D24Tic diesel-engine) and oil cooler.
For the Volvo 700-series Turbo: check all vacuum hoses. They must be in excellent condition, otherwise it will break when being stressed and will cause severe damage on the turbo. Replacing the vacuum hoses is pretty cheap and easy. Be sure the oil return pipe isn’t leaking.
Air filter thermostat valve in your Volvo 700-series car
In the airbox (where the air filter is installed) there is a small thermostat valve which will break during the years. It controls the shutter valve in the airbox, which regulates the flow of hot (pre-heated air coming from the engine by the crappy aluminum hose) or cold air. If this thermostat valve is broken, your car might have troubles running idle when you start the car with a warm engine (the problem disappears after a few miles, but it’s in most cases causes by this broken valve) and fuel consumption will be slightly worse. When the thermostat valve is broken, it could also damage the mass airflow sensor (MAF). Replacing the thermostat valve is easy and not expensive (only a couple of bucks). The Volvo part number is 1266826.
Checking the electrics of your Volvo 740, 760 or 780
Be sure the battery and alternator are in good condition (check it with a voltmeter). Clean the battery terminals and clean them. The old type Volvo 740 and 760 are very sensitive for rotting harnesses. Check all engine wiring harnesses and protect them with tape or replace some wires. Also clean all engine- and chassis grounds: a bad ground can give some nasty errors and failures.
For a detailed inspection I’ll suggest to read the Volvo 700-series buyers guide. It provides all info about the weaknesses of our beloved Volvos and gives you a lot of details which needs a close look. Tutorials about common problems or replacing parts can be found in the Volvo 700-series tutorial section (which will be updated regularly with new how-to tutorials). Any questions or comments? Feel free to mail me: email@example.com.
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